UNDERWRITING AGREEMENT

Exhibit 1.1

UPFC AUTO RECEIVABLES TRUST 2006-B

$250,000,000 AUTOMOBILE RECEIVABLES BACKED NOTES

UPFC AUTO FINANCING CORPORATION

(SELLER)

UNITED AUTO CREDIT CORPORATION

(SERVICER AND SPONSOR)

UNDERWRITING AGREEMENT

December 6, 2006

Deutsche Bank Securities Inc.

as Underwriter

60 Wall Street, 19 ^th Floor

New York, New York 10005

Ladies and Gentlemen:

SECTION 1. Introduction . UPFC Auto Financing Corporation (the “Seller”) proposes to cause UPFC Auto Receivables Trust 2006-B (the “Trust”) to issue and sell $55,000,000 principal amount of its Class A-1 Notes (the “Class A-1 Notes”), $96,000,000 principal amount of Class A-2 Notes (the “Class A-2 Notes”) and $99,000,000 principal amount of its Class A-3 Notes (the “Class A-3 Notes,” and together with the Class A-1 Notes and the Class A-2 Notes, the “Notes”) to Deutsche Bank Securities Inc., as underwriter (the “Underwriter”). The Notes will be issued pursuant to an Indenture, to be dated as of December 1, 2006 (the “Indenture”), between the Trust and Deutsche Bank Trust Company Americas, as indenture trustee (in such capacity, the “Indenture Trustee”) and trust collateral agent. The assets of the Trust will include, among other things, a pool of motor vehicle retail installment sale contracts originated by third-party dealers and then acquired by United Auto Credit Corporation (“UACC”) and sold to the Trust on the Closing Date (the “Receivables”) secured by new and used automobiles, light-duty trucks, sports utility vehicles and vans financed thereby (the “Vehicles”), certain monies received thereunder after the close of business on November 30, 2006 (the “Cutoff Date”), and the other property and the proceeds thereof to be conveyed to the Trust pursuant to the Sale and Servicing Agreement to be dated as of December 1, 2006 (the “Sale and Servicing Agreement”) among the Trust, the Seller, UACC, as Servicer, Deutsche Bank Trust Company Americas and Centerone Financial Services LLC, (the “Designated Backup Subservicer”). Pursuant to the Sale and Servicing Agreement, the Seller will sell the Receivables to the Trust and UACC will service the Receivables on behalf of the Trust. The Seller formed the Trust pursuant to a trust agreement, and it will be governed by an Amended and Restated Trust Agreement (the “Trust Agreement”) to be dated as of December 14, 2006 among the Seller and Wells Fargo Delaware Trust Company, as owner trustee (the “Owner Trustee”). The owner trust certificate (the “Certificate”), representing a fractional undivided interest in the Trust, will be issued to the Seller pursuant to the Trust Agreement.

The Seller will acquire the Receivables from UACC pursuant to the terms of the Sale Agreement (the “Sale Agreement”) dated as of December 1, 2006 between the Seller and UACC. UACC has acquired the Receivables from third-party dealers (the “Dealers”) pursuant to certain dealer retail agreements between each Dealer and UACC (collectively, the “Dealer Retail Agreements”).

Ambac Assurance Corporation (the “Insurer”) has agreed to indemnify UACC and the Underwriter and UACC and the Underwriter have each agreed to indemnify the Insurer pursuant to an Indemnification Agreement, dated as of December 14, 2006 (the “Indemnification Agreement”).

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The Notes will be covered by a Note Guaranty Insurance Policy (the “Policy”) issued by the Insurer, pursuant to an Insurance and Indemnity Agreement, dated as of December 14, 2006 (the “Insurance Agreement”) among the Insurer, the Trust, UACC, the Seller, the Indenture Trustee, the Trust Collateral Agent and the Backup Servicer.

The Trust will pledge to the Collateral Agent a lien and security interest in all of its right, title and interest in the Spread Account pursuant to the terms of the Spread Account Agreement, dated as of December 14, 2006, among the Trust, the Insurer and the Indenture Trustee, the Trust Collateral Agent and the Collateral Agent.

Capitalized terms used but not otherwise defined in this Underwriting Agreement (this “Agreement”) shall have the meanings set forth in the Sale and Servicing Agreement or if not defined therein, then as defined in the Prospectus Supplement (as defined in Section 2(i) below). As used herein, the term “Transaction Documents” refers to the Sale and Servicing Agreement, the Indenture, the Spread Account Agreement, the Trust Agreement, the Insurance Agreement, the Indemnification Agreement, the Policy and the Sale Agreement.

At or prior to the time when sales to purchasers of the Notes were first made to investors by the Underwriter, which was approximately 12:30 a.m. on December 6, 2006 (the “Time of Sale”), the Seller had prepared the Preliminary Prospectus Supplement dated December 6, 2006 to the Prospectus dated November 17, 2006 (along with information referred to under the caption “Static Pool Data” therein regardless of whether it is deemed a part thereof under the Rules and Regulations (as defined in Section 2(ii) below), together the “Preliminary Prospectus”). If, subsequent to the Time of Sale and prior to the Closing Date, such information included an untrue statement of material fact or omitted to state a material fact necessary in order to make the statements therein, in light of the circumstances under which they were made, not misleading and the Underwriter terminates its old “Contracts of Sale” (within the meaning of Rule 159 under the Securities Act) and enters into new Contracts of Sale with investors in the Notes, then the “Preliminary Prospectus” will refer to the information conveyed to investors at the time of entry into such new Contract of Sale, in an amended Preliminary Prospectus approved by the Seller and the Underwriter that corrects such material misstatements or omissions (a “Corrected Prospectus”) and “Time of Sale” will refer to the time and date on which such new Contracts of Sale were entered into.

SECTION 2. Representations and Warranties . (a) As a condition of the obligations of the Underwriter to purchase the Notes, each of the Seller and UACC makes the representations and warranties set forth below to the Underwriter. To the extent a representation or warranty specifically relates to the Seller, such representation or warranty is made by the Seller and UACC jointly, and to the extent a representation or warranty specifically relates solely to UACC, such representation or warranty is only made by UACC and not by the Seller.

(i) The registration statement on Form S-3 (No. 333-137374), including the exhibits thereto, has been filed with the Securities and Exchange Commission (the “Commission”) for registration under the Securities Act, which registration statement has been declared effective by the Commission within the three years prior to the Closing Date and is still effective as of the date hereof. Such registration statement, including the exhibits thereto, as amended to the date hereof, is hereinafter called the “Registration

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Statement”; the prospectus included in the Registration Statement, at the time the Registration Statement became effective, or as subsequently filed with the Commission pursuant to Rule 424(b) under the Securities Act is hereinafter called the “Base Prospectus”; a prospectus supplement relating to the Notes, in the form first filed after the date hereof pursuant to Rule 424(b) under the Securities Act, including the Base Prospectus as so supplemented and together, along with information referred to under the caption “Static Pool Data” therein regardless of whether it is deemed a part of the Registration Statement or Base Prospectus under the Rules and Regulations, is hereinafter called the “Prospectus Supplement”; and the Base Prospectus together with the Prospectus Supplement are hereinafter called the “Prospectus.” Any preliminary form of the Prospectus that has heretofore been filed pursuant to Rule 424(b) is hereinafter called a “preliminary prospectus.” Any reference herein to the terms “amend,” “amendment” or “supplement” with respect to the Registration Statement, the Base Prospectus or the Prospectus Supplement, shall be deemed to refer to and include the filing of any document under the Securities Exchange Act of 1934, as amended (the “Exchange Act”) or the filing date of the Base Prospectus or Prospectus Supplement, as the case may be, deemed to be incorporated therein by reference pursuant to Item 12 of Form S-3 under the Securities Act.

(ii) The Registration Statement as of the applicable effective date as to each part thereof pursuant to Rule 430B(f)(2) and any amendment thereto under the Securities Act (the “Effective Date”) and as of the Time of Sale, the Preliminary Prospectus, as of the date of the Time of Sale, and the Prospectus, as of the date of the Prospectus Supplement, complied in all material respects with the applicable requirements of the Securities Act and the rules and regulations of the Commission thereunder (the “Rules and Regulations”); and the information in the Registration Statement, as of the Effective Date and as of the Time of Sale, will conform in all material respects to the requirements of the Securities Act and the Rules and Regulations and did not contain any untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein not misleading; the Preliminary Prospectus, as of the date of the Time of Sale and as of the Closing Date, will conform in all material respects to the requirements of the Securities Act and the Rules and Regulations; and the Prospectus, and any amendments thereof and supplements thereto, as of the date of the Prospectus Supplement and as of the Closing Date, will conform in all material respects to the requirements of the Securities Act and the Rules and Regulations and will not include any untrue statement of a material fact or omit to state a material fact necessary to make the statements therein, in the light of the circumstances under which they are made, not misleading; provided, however, that neither UACC nor the Seller makes any representations or warranties as to (i) that part of the Registration Statement which constitutes the Statement of Qualification under the Trust Indenture Act of 1939, as amended (the “Trust Indenture Act”) on Form T-1 (the “Form T-1”) of the Indenture Trustee (which will be represented and warranted to by the Indenture Trustee) and (ii) the information contained in or omitted from such Registration Statement or such Prospectus (or any supplement thereto) in reliance upon and in conformity with written information furnished to UACC by the Underwriter specifically for use in the preparation thereof which information consists solely of the information set forth in the chart following the

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second paragraph, the third, the fourth, the fifth and the sixth paragraph under the heading “Underwriting” in the Prospectus Supplement (the “Underwriter’s Information”).

(iii) The Preliminary Prospectus, at the Time of Sale, did not, and at the Closing Date will not, contain any untrue statement of a material fact or omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading; provided that the Seller makes no representation and warranty with respect to any statements or omissions made in reliance upon and in conformity with the Underwriter’s Information.

(iv) Since the respective dates as of which information is given in the Preliminary Prospectus and in the Prospectus there has not been any material adverse change, or, to the best of our knowledge, any development involving a prospective material adverse change, in or affecting the condition, financial or otherwise, earnings, business or operations of any of UACC or its subsidiaries, including the Seller and its subsidiaries, taken as a whole, except as disclosed to the Underwriter in writing prior to the date hereof.

(v) The Indenture has been qualified under the Trust Indenture Act.

(vi) The Trust Agreement is not required to be qualified under the Trust Indenture Act.

(vii) The Trust is not required to register under the Investment Company Act of 1940, as amended (the “Investment Company Act”).

(viii) The issuance and sale of the Notes have been duly authorized by all necessary corporate action of the Seller and, when executed, authenticated and delivered to and paid for by the Underwriter in accordance with the terms of this Agreement and the Indenture, the Notes will be valid and binding obligations of the Trust, enforceable in accordance with their terms, except to the extent that the enforceability thereof may be subject to bankruptcy, insolvency, reorganization, receivership, conservatorship, moratorium or other similar laws now or hereafter in effect relating to creditors’ rights in general and to general principles of equity.

(ix) Each of the Seller and UACC has been duly incorporated and is validly existing as a corporation in good standing under the law of its jurisdiction of incorporation with full corporate power and authority to own, lease and operate its properties and assets and conduct its business as described in the Preliminary Prospectus and the Prospectus, is duly qualified to transact business and is in good standing in each jurisdiction in which its ownership, leasing or operation of its properties or assets or the conduct of its business requires such qualification, except where the failure to be in good standing would not have a material adverse effect on the ability of the Seller or UACC to perform its respective obligations under the Agreement and the Transaction Documents or on the consummation of the transactions as contemplated by the Transaction Documents, and has full corporate power and authority to execute and perform its obligations under this Agreement and the Transaction Documents to which it is a party.

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(x) The execution and delivery of this Agreement have been duly authorized by all necessary corporate action of the Seller and UACC, and this Agreement has been duly executed and delivered by the Seller and UACC and when duly executed and delivered by the other parties hereto will be the legal, valid and binding agreement of the Seller and UACC, enforceable against the Seller and UACC in accordance with its terms, except to the extent that the enforceability thereof may be subject to bankruptcy, insolvency, reorganization, receivership, conservatorship, moratorium or other similar laws now or hereafter in effect relating to creditors’ rights in general; to general principles of equity; and to limitations as to rights of indemnity under applicable securities laws.

(xi) The execution and delivery of the Transaction Documents to which it is a party have been duly authorized by all necessary corporate action of the Seller or UACC, as applicable, and, when duly executed and delivered by the Seller and UACC (assuming due authorization, execution and delivery by the other parties thereto), will be legal, valid and binding agreements of the Seller and UACC, enforceable against the Seller or UACC in accordance with their respective terms, except to the extent that the enforceability thereof may be subject to bankruptcy, insolvency, reorganization, receivership, conservatorship, moratorium or other similar laws now or hereafter in effect relating to creditors’ rights in general and to general principles of equity.

(xii) The execution and delivery by each of the Seller and UACC of, and the performance by each of the Seller and UACC of its obligations under, this Agreement, each of the Transaction Documents to which it is a party and the Seller under the Notes, the issuance and sale of the Notes to the Underwriter by the Seller pursuant to this Agreement (subject to obtaining any consents or approvals as may be required under the securities or “blue sky” laws to various jurisdictions), the compliance by the Seller and UACC with the other provisions of this Agreement and the consummation of the other transactions herein contemplated do not (x) require the consent, approval, authorization, registration or qualification of or with any governmental authority, except as such have been obtained or made or such as may be required under the securities or “blue sky” laws of various jurisdictions, or (y) conflict with or result in a breach or violation or acceleration of, or constitute a default under, any term or provision of the organizational documents of the Seller or UACC, any indenture mortgage, deed of trust, lease or other agreement or instrument to which the Seller or UACC is a party or by which any of them or their properties is bound or result in a violation of or contravene the terms of any statute, order or regulation applicable to the Seller or UACC of any court, regulatory body, administrative agency, governmental body or arbitrator having jurisdiction over the Seller or UACC, or result in the creation of any lien upon any property or assets of the Seller or UACC (other than pursuant to the Transaction Documents), except where such conflict, breach, default or creation would not have a material adverse effect on the ability of the Seller and UACC to perform its respective obligations under the Agreement and the Transaction Documents or on the consummation of the transactions as contemplated by the Transaction Documents.

(xiii) None of the Seller or UACC is in violation of any term or provision of its charter documents or by-laws, or in breach of or in default under any statute or any

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judgment, decree, order, rule or regulation of any court or other governmental authority or any arbitrator applicable to the Seller or UACC, the consequence of which violation, breach or default would have (a) a materially adverse effect on or constitute a materially adverse change in the condition (financial or otherwise), earnings, properties, business affairs, net worth or results of operations of the Seller or UACC or (b) a material and adverse effect on its ability to perform its obligations under this Agreement or any of the Transaction Documents, in each case, to which it is a party.

(xiv) None of the Seller, UACC nor anyone acting on their behalf has taken any action that would require registration of the Seller or the Trust under the Investment Company Act; nor will the Seller nor UACC act, nor has either of them authorized nor will either of them authorize any person to act, in such manner.

(xv) Each of the Seller and UACC possesses all consents, licenses, certificates, authorizations and permits issued by the appropriate federal, state or foreign regulatory authorities necessary to conduct their respective businesses, the absence of which would have a material adverse effect on the ability of the Seller and UACC to perform its respective obligations under the Agreement and the Transaction Documents or on the consummation of the transactions as contemplated by the Transaction Documents, and neither the Seller nor UACC has received any notice of proceedings relating to the revocation or modification of any such license, certificate, authorization or permit which, singly or in the aggregate, if the subject of an unfavorable decision, ruling or finding, would have a materially adverse effect on or constitute a materially adverse change in the condition (financial or otherwise), earnings, properties, business affairs, net worth or results of operations of the Seller or UACC, except as described in or contemplated by the Prospectus.

(xvi) No legal or governmental proceedings are pending or threatened to which the Seller or UACC is a party or to which the property of the Seller or UACC is subject except for such proceedings that would not, if the subject of any unfavorable decision, ruling or finding, singly or in the aggregate, have a material adverse effect on the condition (financial or otherwise), earnings, properties, business affairs, net worth or results of operations of the Seller or UACC or the Seller’s or UACC’s ability to perform its obligations under this Agreement or the Transaction Documents or on the consummation of the transactions as contemplated by the Transaction Documents.

(xvii) No default exists, and no event has occurred which, with notice or lapse of time or both, would constitute a default in the due performance and observance of any term, covenant or condition of any material indenture, mortgage, deed of trust, lease or other material agreement or instrument to which the Seller or UACC is a party or by which the Seller or UACC or any of its respective properties is bound.

(xviii) The Notes and the Transaction Documents conform in all material respects to the descriptions thereof contained in the Preliminary Prospectus and in the Prospectus.

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(xix) Each of the Seller’s and UACC’s representations and warranties in the Transaction Documents are true and correct as of the date they are given therein and will be true and correct on the Closing Date, and such representations and warranties are incorporated herein by reference.

(xx) Other than as contemplated by this Agreement or as disclosed in the Preliminary Prospectus and in the Prospectus, there is no broker, finder or other party that is entitled to receive from the Seller or any of its Affiliates or the Underwriter, any brokerage or finder’s fee or other fee or commission as a result of any of the transactions contemplated by this Agreement.

(xxi) None of the Seller, UACC nor any of their Affiliates has entered into, nor will it enter into, any contractual arrangement with respect to the distribution of the Notes except for this Agreement.

(xxii) Assuming that the Notes are issued in accordance with the provisions of the Indenture and distributed in accordance with the terms of the Agreement and as described in the Prospectus, the Notes are “asset backed securities” within the meaning of, and satisfy the requirements for use of, Form S-3 under the Securities Act.

(xxiii) The Notes, when duly and validly executed by the Indenture Trustee, authenticated and delivered in accordance with the Indenture, and delivered and paid for pursuant hereto will be validly issued and outstanding and entitled to the benefits of the Indenture.

(xxiv) The Certificates, when duly and validly executed by the Owner Trustee, authenticated and delivered in accordance with the Trust Agreement, will be validly issued and outstanding and entitled to the benefits of the Trust Agreement.

(xxv) Any taxes, fees and other governmental charges due on or prior to the Closing Date (including, without limitation, sales taxes) in connection with the execution, delivery and performance of this Agreement and the Transaction Documents and the issuance of the Notes have been or will have been paid at or prior to the Closing Date.

(xxvi) None of the transactions contemplated by this Agreement (including, without limitation, the use of the proceeds from the sale of the Notes) will violate or result in a violation of Section 7 of the Exchange Act, or any regulation promulgated thereunder, including, without limitation, Regulations T, U, and X of the Board of Governors of the Federal Reserve System.

(xxvii) As of the Time of Sale, the Seller was not and as of the Closing Date is not, an “ineligible issuer,” as defined in Rule 405 under the Securities Act.

(xxviii) The Seller has filed the Preliminary Prospectus and each Free Writing Prospectus required to have been filed under the Securities Act and the Rules and Regulations and it has done so within the applicable periods of time required under the Securities Act and the Rules and Regulations; provided, however that no Free Writing Prospectus has been filed with respect to this transaction.

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(xxix) Prior to the date hereof, none of UACC, the Seller nor any of their Affiliates (including, without limitation, all officers and directors thereof) has taken any action which is designed to or which has constituted or which might have been expected to cause or result in stabilization or manipulation of the price of any security in connection with the offering of the Notes.

(b) The above representations and warranties shall be deemed to be repeated in their entirety at and as of the Closing Date.

(c) The Underwriter hereby makes the representations and agrees to the statements contained in Annex A hereto.

SECTION 3. Purchase, Sale and Delivery of Notes . (a) On the basis of the representations, warranties and agreements herein contained, but subject to the terms and conditions herein set forth, the Seller agrees to cause the Trust to sell to the Underwriter, and the Underwriter agrees to purchase from the Trust the Notes, at a purchase price (the “Purchase Price”) equal to “$249,478,911.30”. Delivery of and payment for the Notes shall be made at the offices of Mitchell Silberberg & Knupp LLP, 11377 West Olympic Boulevard, Los Angeles, California 90064-1683 at 10:00 a.m. (New York time) on December 14, 2006 (or at such other place and time on the same or other date as shall be agreed to in writing by the Underwriter and the Seller, the “Closing Date”). Delivery of one or more global notes representing the Notes shall be made against payment of the aggregate purchase price in immediately available funds drawn to the order of the Seller. The global notes to be so delivered shall be registered in the name of Cede & Co., as nominee of The Depository Trust Company (“DTC”). The interests of beneficial owners of the Notes will be represented by book entries on the records of DTC and participating members thereof. Definitive Notes representing the Notes will be available only under limited circumstances, as described in the Prospectus.

(b) The Seller hereby acknowledges that the payment of monies pursuant to Section 3(a) hereof (a “Payment”) by the Underwriter of the aggregate Purchase Price for the Notes does not constitute closing of a purchase and sale of the Notes. Only (1) the execution and delivery, by facsimile or otherwise, of a receipt for Notes by the Underwriter, and (2) the release of all Permitted Liens, by 4:00 p.m. (New York time) on the Closing Date, indicates completion of the closing of a purchase of the Notes from the Trust. Furthermore, in the event that the Underwriter makes a Payment to the Trust prior to the completion of the closing of a purchase of Notes, the Seller hereby acknowledges that until the Underwriter executes and delivers such receipt for the Notes and until all Permitted Liens have been released by or before 4:00 p.m. (New York time) on the Closing Date, the Trust will not be entitled to the Payment and the Seller shall cause the Trust to return the Payment to the Underwriter as soon as practicable (by wire transfer of same-day funds) upon demand. In the event that the closing of a purchase of Notes is not completed and the Payment is not returned by the Trust to the Underwriter on the same day the Payment was received by the Trust, the Seller agrees to pay, or otherwise cause the Trust to pay, to the Underwriter in respect of each day the Payment is not returned by it, in same-day funds, interest on the amount of such Payment in an amount representing the Underwriter’s cost of financing as reasonably determined by the Underwriter.

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SECTION 4. Offering by the Underwriter . Upon the authorization by the Underwriter of the release of the Notes, the Underwriter proposes to offer the Notes for sale upon the terms and conditions set forth in this Agreement and the Prospectus.

SECTION 5. Covenants of the Seller and UACC . Each of the Seller and UACC covenants and agrees with the Underwriter as set forth below.

(a) To file the Prospectus, properly completed, with the Commission pursuant to and in accordance with Rule 424(b) under the Securities Act no later than the second business day following the day it is first used. The Seller will file with the Commission any Free Writing Prospectus delivered to investors in accordance with Section 6 as the Seller is required to file under the Securities Act and the Rules and Regulations, and to do so within the applicable period of time required under the Securities Act and the Rules and Regulations (which for the avoidance of doubt shall be in the case of a Free Writing Prospectus that is Pre-pricing and Pricing Information, the final version of the Pre-pricing and Pricing Information); provided, as to any Free Writing Prospectus delivered by the Underwriter, the Seller is given timely notice and copies of such Free Writing Prospectus. The Seller or UACC will advise the Underwriter promptly of any such filing under the Securities Act.

(b) To furnish to the Underwriter and counsel for the Underwriter, without charge, as many copies of the Registration Statement, Preliminary Prospectus and the Prospectus and all amendments and supplements to such documents, in each case as soon as available and in such quantities as the Underwriter reasonably requests. The Prospectus shall be furnished on or prior to 12:00 noon, New York time, on or prior to the second business day preceding the Closing Date. All other documents shall be so furnished as soon as available and in such quantities as the Underwriter may reasonably request. The Seller or UACC will pay the expenses of printing, reproducing and distributing to the Underwriter all such documents.

(c) To advise the Underwriter promptly, in writing, of any proposal to amend or supplement the Registration Statement or the Prospectus and will not effect any such amendment or supplement to which the Underwriter shall reasonably object; and to also advise the Underwriter promptly of the effectiveness of each Registration Statement and of any amendment or supplement of the Registration Statement or the Prospectus and of the institution by the Commission of any stop order proceedings in respect of the Registration Statement and will use its best efforts to prevent the issuance of any such stop order and to obtain as soon as possible its lifting, if issued.

(d) To furnish the Underwriter with copies of the Preliminary Prospectus and the Prospectus and each amendment or supplement, during the period when any Underwriter is required to deliver a Prospectus under the Securities Act, at the cost and expense of UACC, each in such quantities as the Underwriter may from time to time reasonably request (and subsequent to such period, to assist the Underwriter in obtaining sufficient additional copies of the Prospectus, at the cost and expense of the Underwriter); and if, at any time prior to the expiration of the Prospectus delivery period under the Securities Act, any event shall have occurred as a result of which the Prospectus as then amended or supplemented would include an untrue statement of a material fact or omit to state any material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made when such

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Prospectus is delivered, not misleading, or, if for any other reason it shall be necessary or desirable during such same period to amend or supplement the Prospectus, to notify the Underwriter and promptly prepare and file with the Commission (subject to the Underwriter’s prior review pursuant to Section 5(c)), at its own expense, an amendment or supplement which will correct such statement or omission, or an amendment which will effect such compliance. Upon the Underwriter’s request, the Seller will prepare and furnish without charge to the Underwriter and to any dealer in securities as many written and electronic copies as the Underwriter may from time to time reasonably request of an amended Prospectus or a supplement to the Prospectus which will correct such statement or omission or effect such compliance. Neither the Underwriter’s consent to, nor the Underwriter’s distribution of any amendment or supplement to the Prospectus shall constitute a waiver of any of the conditions set forth in Section 8 hereof.

(e) The Seller will arrange for the qualification of the Notes for offering and sale in each jurisdiction as the Underwriter shall designate including, but not limited to, pursuant to applicable state securities (“Blue Sky”) laws of certain states of the United States of America or other U. S. jurisdictions so designated, and the Seller shall maintain such qualifications in effect for so long as may be necessary in order to complete the placement of the Notes; provided, however, that the Seller shall not be obliged to file any general consent to service of process or to qualify as a foreign corporation or as a securities dealer in any jurisdiction or to subject itself to taxation in respect of doing business in any jurisdiction in which it is not otherwise so subject. The Seller will promptly advise the Underwriter of the receipt by the Seller of any notification with respect to the suspension of the qualification of the Notes for sale in any jurisdiction or the initiation or threatening of any proceeding for such purpose.

(f) The Seller will cooperate with the Underwriter and use its best efforts to permit the Notes to be eligible for clearance and settlement through DTC.

(g) UACC and the Seller shall (i) furnish or make available to the Underwriter or its counsel such additional documents and information regarding UACC, the Seller and their respective affairs as the Underwriter may from time to time reasonably request prior to the Closing Date, including any and all documentation reasonably requested in connection with its due diligence efforts regarding information in the Registration Statement and the Prospectus and in order to evidence the accuracy or completeness of any of the conditions contained in this Agreement and (ii) provide the Underwriter or its advisors, or both, prior to acceptance of its subscription, the opportunity to ask questions of, and receive answers with respect to such matters.

(h) From the date hereof until the Closing Date, none of the Seller, UACC, nor any of their respective Affiliates will, without the prior written consent of the Underwriter, directly or indirectly, offer, sell or contract to sell or announce the offering of, in a public or private transaction, any other collateralized securities similar to the Notes.

(i) During the period beginning on the Closing Date and continuing until and including the date that is six months after the Closing Date, none of the Seller, UACC or any of their Affiliates shall offer, sell, contract to sell or otherwise dispose of any securities of the Trust, the Seller or UACC in a public offering that are substantially similar to the Notes, without first

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furnishing to the Underwriter an opinion of counsel (in form and from such firm as is reasonably satisfactory to the Underwriter and counsel to the Underwriter) stating that such public offering of securities would not result in any violation of federal or state securities laws with respect to the Notes.

(j) Until the retirement of the Notes, neither the Seller nor UACC shall, nor cause the Trust to, be or become an investment company that is or is required to be registered under Section 8 of the Investment Company Act.

(k) Until the retirement of the Notes, or until the Underwriter no longer maintains a secondary market in the Notes, whichever occurs first, UACC shall cause the Seller to and the Seller shall deliver to the Underwriter the annual statement of compliance and any annual independent certified public accountants’ report furnished to the Indenture Trustee pursuant to the Sale and Servicing Agreement, as soon as such statements and reports are furnished to the Indenture Trustee.

(l) So long as any of the Notes are outstanding, UACC shall cause the Seller to and the Seller shall deliver to the Underwriter: (i) all documents distributed to Noteholders and (ii) from time to time, any other information concerning UACC, the Seller or the Trust as the Underwriter may reasonably request only insofar as such information reasonably relates to the Registration Statement, the Prospectus or the transactions contemplated by the Transaction Documents.

(m) On or before the Closing Date, UACC and the Seller (to the extent applicable) shall each cause their computer records relating to the Receivables to be marked to show the Trust’s absolute ownership of the Receivables, and from and after the Closing Date neither the Seller nor UACC shall take any action inconsistent with the Trust’s ownership of such Receivables, other than as permitted by the Indenture or the Sale and Servicing Agreement.

(n) To the extent, if any, that any of the ratings assigned to the Notes by any of the rating agencies that initially rate the Notes are conditional upon the furnishing of documents or the taking of any other actions by the Seller or UACC, as the case may be, the relevant party shall furnish, or cause to be furnished, such documents and take any such other actions as promptly as possible.

(o) The Seller or UACC will cause the Trust to make generally available to Noteholders, as soon as practicable, but no later than sixteen months after the date hereof, an earnings statement of the Trust covering a period of at least twelve consecutive months beginning after the later of (i) the Effective Date of the Registration Statement relating to the Notes and (ii) the effective date of the most recent post-effective amendment to the Registration Statement to become effective prior to the date of this Agreement, it being understood that timely delivery of each Servicer’s Certificate pursuant to Section 4.9 of the Sale and Servicing Agreement satisfies this covenant.

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SECTION 6. Preliminary Prospectus and Free Writing Prospectus .

(a) The following terms have the specified meanings for purposes of this Agreement:

(i) “ Free Writing Prospectus ” means and includes any information relating to the Offered Notes disseminated by the Seller or any Underwriter that constitutes a “free writing prospectus” within the meaning of Rule 405 under the Securities Act.

(ii) “ Issuer Information ” means the information contained in the Preliminary Prospectus (other than Underwriter’s Information), any Free Writing Prospectus (other than an Underwriter Free Writing Prospectus) and the Underwriter Free Writing Prospectus (solely limited to (A) information included in the Preliminary Prospectus and (B) Pre-pricing and Pricing Information).

(iii) “ Underwriter Free Writing Prospectus ” means a Free Writing Prospectus prepared by or on behalf of an Underwriter.

(iv) “ Pre-pricing and Pricing Information ” means the information in an Underwriter Free Writing Prospectus consisting of (A) the status of the subscriptions for each class of Notes, (B) weighted average lives, ratings, expected maturities and/or payment windows, benchmarks and legal finals for each class of Notes, (B) expected or actual pricing parameters for each class of Notes, (C) expected settlement and non offered notes and (D) CUSIP numbers, ERISA eligibility, pricing prepayment speed and clean up call.

(b) The Seller will not disseminate to any potential investor any information relating to the Notes that constitutes a “written communication” within the meaning of Rule 405 under the Securities Act, other than the Preliminary Prospectus and the Prospectus unless the Seller has obtained the prior consent of the Underwriter.

(c) Neither the Seller nor the Underwriter shall disseminate or file with the Commission any information relating to the Notes in reliance on Rule 167 or 426 under the Securities Act, nor shall the Seller or the Underwriter disseminate any Free Writing Prospectus “in a manner reasonably designed to lead to its broad unrestricted dissemination” within the meaning of Rule 433(d) under the Securities Act.

(d) Each Free Writing Prospectus shall bear the following legend, or a substantially similar legend that complies with Rule 433 under the Securities Act:

The Seller has filed a registration statement (including a prospectus) with the SEC for the offering to which this communication relates. Before you invest, you should read the prospectus in that registration statement and other documents the depositor has filed with the SEC for more complete information about the depositor, the issuing trust, and this offering. You may get these documents for free by visiting EDGAR on the SEC Web site at www.sec.gov. Alternatively, the depositor, any underwriter or any dealer participating in the offering will arrange to send you the prospectus if you request it by calling toll-free 1-(866) 669-7629.

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(e) In the event that the Seller or UACC become aware that, as of the Time of Sale, any Preliminary Prospectus contains or contained any untrue statement of material fact or omits or omitted to state a material fact necessary in order to make the statements contained therein, in light of the circumstances under which they were made, not misleading (a “Defective Prospectus”), such entity shall promptly notify the Underwriter of such untrue statement or omission no later than one business day after discovery and the Seller shall, if requested by the Underwriter, prepare and deliver to the Underwriter a Corrected Prospectus.

(f) The Underwriter represents, warrants, covenants and agrees with the Seller that:

(i) It has not provided and will not provide to any potential investor any information that would constitute “written communication” (as defined in Rule 405 under the Securities Act) that constitutes an offer to sell or solicitation of an offer to buy the Notes, including, but not limited to any “ABS informational and computational materials” as defined in Item 1101(a) of Regulation AB under the Securities Act; other than that contained in one or more of (a) an Underwriter Free Writing Prospectus (consisting of information limited to (1) information included in the previously filed Preliminary Prospectus, (2) Pre-pricing and Pricing Information, (3) Intex .cdi files and (4) information customarily included in confirmations of sales of securities and notices of allocations), (b) the Preliminary Prospectus, (c) the Prospectus, and (d) information delivered in compliance with Rule 134 of the Securities Act.

(ii) In disseminating information to prospective investors, it has complied and will continue to comply fully with the Rules and Regulations, including but not limited to Rules 164 and 433 under the Securities Act and the requirements thereunder for filing and retention of Free Writing Prospectuses, including retaining any Free Writing Prospectuses they have used but which are not required to be filed for the required period.

(iii) Prior to entering into any Contract of Sale, the Underwriter shall convey the Preliminary Prospectus to the prospective investor. The Underwriter shall maintain sufficient records to document its conveyance of the Preliminary Prospectus to the potential investor prior to the formation of the related Contract of Sale and shall maintain such records as required by the Rules and Regulations.

(iv) If a Defective Prospectus has been corrected with a Corrected Prospectus delivered to the Underwriter, it shall (A) deliver the Corrected Prospectus to each investor with whom it entered into a Contract of Sale and that received the Defective Prospectus from it prior to entering into a new Contract of Sale with such investor, (B) notify such investor in a prominent fashion that the prior Contract of Sale with the investor, if any, has been terminated and of the investor’s rights as a result of such agreement and (C) provide such investor with an opportunity to affirmatively agree to purchase the Notes on the terms described in the Corrected Prospectus.

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(g) The Underwriter shall deliver to the Seller, not less than one business day prior to the required date of filing thereof, all information included in an Underwriter Free Writing Prospectus required to be filed with the Commission under the Securities Act.

(h) In the event that the Underwriter shall incur any costs to any investor in connection with the reformation of the Contract of Sale with such investor that received a Defective Prospectus (except to the extent the Defective Prospectus results solely from statements or omissions made in reliance upon and in conformity with the Underwriter’s Information), the Seller and UACC jointly and severally agree to reimburse the Underwriter for such costs. In the event the Seller or UACC shall incur any costs in connection with a Defective Prospectus (to the extent the Defective Prospectus results solely from statements or omissions made in reliance upon and in conformity with the Underwriter’s Information), the Underwriter shall reimburse the Seller or UACC, as applicable, for such costs.

SECTION 7. Payment of Expenses . UACC will pay all expenses incident to the transactions contemplated by this Agreement, whether or not the transactions contemplated herein are consummated or this Agreement is terminated pursuant to Section 9 hereof, including: (a) the preparation, printing and distribution of the Registration Statement, the Preliminary Prospectus and the Prospectus Supplement and each amendment or supplement thereto and delivery of copies thereof to the Underwriter, (b) the preparation of this Agreement, (c) the preparation, issuance and delivery of the Notes to the Underwriter (or any appointed clearing organizations), (d) the fees and disbursements of UACC’s and the Seller’s accountants, (e) the qualification of the Notes under state securities laws including filing fees and the fees and disbursements of counsel to the Underwriter in connection therewith and in connection with the preparation of any Blue Sky survey (including the printing and delivery thereof to the Underwriter), (f) any fees charged by rating agencies for the rating (or consideration of the rating) of the Notes, (g) the fees and expenses incurred with respect to any filing with, and review by, DTC or any similar organizations, (h) the fees and disbursements of the Indenture Trustee and its counsel, if any, (i) the fees and disbursements of the Owner Trustee and its counsel, if any, (