MORTGAGE LOAN PURCHASE AGREEMENT DATED AS

Exhibit 4.8

[                                           ]

AS PURCHASER,

[                                           ]

AS SELLER

AND

[                                           ]

MORTGAGE LOAN PURCHASE AGREEMENT

DATED AS OF [                              ]

ADJUSTABLE-RATE AND FIXED-RATE MORTGAGE LOANS

[              ] SERIES [              ]

TABLE OF CONTENTS

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This MORTGAGE LOAN PURCHASE AGREEMENT (this “Agreement”), dated as of [                              ], is made among [                                           ] (the “Seller”) and [                                           ] (the “Purchaser”).

W I T N E S S E T H :

WHEREAS, the Seller owns the Mortgage Loans indicated on the Mortgage Loan Schedule attached as Exhibit 1 hereto (the “Mortgage Loans”), including rights to (a) any property acquired by foreclosure or deed in lieu of foreclosure or otherwise, and (b) the proceeds of any insurance policies covering the Mortgage Loans;

WHEREAS, the parties hereto desire that the Seller sell the Mortgage Loans to the Purchaser (other than the servicing rights with respect thereto), that the Seller make certain representations and warranties and undertake certain obligations with respect to the Mortgage Loans;

WHEREAS, pursuant to the terms of a Pooling and Servicing Agreement (the “Pooling and Servicing Agreement”) dated as of [                              ], among the Purchaser, as depositor, [                                           ], as servicer and [                                           ], as trustee (the “Trustee”), the Purchaser will issue the Mortgage Pass-Through Certificates, Series [              ] (the “Certificates”);

NOW, THEREFORE, in consideration of the mutual covenants herein contained, the parties hereto agree as follows:

ARTICLE I

DEFINITIONS

Section 1.1 Definitions . For all purposes of this Mortgage Loan Purchase Agreement, except as otherwise expressly provided herein or unless the context otherwise requires, capitalized terms not otherwise defined herein shall have the meanings assigned to such terms in the Pooling and Servicing Agreement. All other capitalized terms used herein shall have the meanings specified herein.

ARTICLE II

SALE OF MORTGAGE LOANS AND RELATED PROVISIONS

Section 2.1 Sale of Mortgage Loans .

(a) The Seller, by the execution and delivery of this Agreement, does hereby sell, assign, set over, and otherwise convey to the Purchaser, without recourse but subject to the terms of this Agreement, all of its right, title and interest in, to and under the following, whether now existing or hereafter acquired and wherever located, on the Closing Date and as of the Cut-off Date: (i) the Mortgage Loans identified on Exhibit 1 as of the Closing Date, other than the servicing rights with respect thereto.

(b) In connection with such conveyances by the Seller, the Seller shall on behalf of the Purchaser deliver to, and deposit with the Trustee, on or before the Closing Date, the following documents or instruments with respect to each Mortgage Loan:

(i) the original Mortgage Note endorsed without recourse, to the order of the Trustee in blank or, with respect to any Mortgage Loan as to which the original Mortgage Note has been permanently lost or destroyed and has not been replaced, a Lost Note Affidavit;

(ii) the original recorded Mortgage or, if the original Mortgage has not been returned from the public recording office, a copy of the Mortgage certified by the Seller or the public recording office in which such Mortgage has been recorded to be a true and complete copy of the original Mortgage submitted for recording;

(iii) an assignment (which may be included in one or more blanket assignments if permitted by applicable law) of the Mortgage in blank or to the Trustee (or to MERS, if the Mortgage Loan is registered on the MERS ^® System and noting the presence of a MIN) and otherwise in recordable form;

(iv) the original recorded Assignment or Assignments of the Mortgage showing an unbroken chain of assignment from the originator thereof to the Person assigning it to the Trustee or, if any such Assignment has not been returned from the applicable public recording office, a copy of such Assignment certified by the Seller to be a true and complete copy of the original Assignment submitted to the title insurance company for recording;

(v) either (a) the original title insurance policy, or, if such policy has not been issued, any one of an original or a copy of the preliminary title report, title binder or title commitment on the Mortgaged Property with the original policy of the insurance to be delivered promptly following the receipt thereof or (b) a copy of the original title insurance policy;

(vi) a copy of the related hazard insurance policy; and

(vii) a true and correct copy of any assumption, modification, consolidation or substitution agreement.

The Seller shall deliver to the Trustee: (a) either the original recorded Mortgage, or in the event such original cannot be delivered by the Seller, a copy of such Mortgage certified as true and complete by the appropriate recording office, in those instances where a copy thereof certified by the Seller was delivered to the Trustee pursuant to clause (ii) above; and (b) either the original Assignment or Assignments of the Mortgage, with evidence of recording thereon, showing an unbroken chain of assignment from the originator to the Seller, or in the event such original cannot be delivered by the Seller, a copy of such Assignment or Assignments certified as true and complete by the appropriate recording office, in those instances where copies thereof certified by the Seller were delivered to the Trustee pursuant to clause (iv) above. However, the Seller need not cause to be recorded any assignment in any jurisdiction under the laws of which,

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as evidenced by an Opinion of Counsel delivered by the Seller to the Trustee, the Certificate Insurer and the Rating Agencies, the recordation of such assignment is not necessary to protect the Trustee’s interest in the related Mortgage Loan; provided , however , notwithstanding the delivery of any Opinion of Counsel, each assignment shall be submitted for recording by the Seller in the manner described above, at no expense to the Trust or the Trustee, upon the earliest to occur of: (i) reasonable direction by the Holders of Certificates evidencing at least 25% of the Voting Rights, (ii) the occurrence of a Event of Default under the Pooling and Servicing Agreement, (iii) the occurrence of a bankruptcy, insolvency or foreclosure relating to the Seller, (iv) the occurrence of a servicing transfer as described in Section 7.02 of the Pooling and Servicing Agreement and (v) if the Seller is not the Servicer and with respect to any one assignment, the occurrence of a bankruptcy, insolvency or foreclosure relating to the Mortgagor under the related Mortgage.

To the extent an assignment referred to in clause (iii) above is required to be recorded, the Seller at its own expense shall complete and submit it for recording in the appropriate public office for real property records, with such assignment completed in favor of the Trustee. While such assignment to be recorded is being recorded, the Trustee shall retain a photocopy of such assignment. If any assignment is lost or returned unrecorded to the Trustee because of any defect therein, the Seller is required to prepare a substitute assignment or cure such defect, as the case may be, and the Seller shall cause such substitute assignment to be recorded in accordance with this paragraph.

In connection with the assignment of any Mortgage Loan registered on the MERS ^® System, the Seller further agrees that it will cause, at the Seller’s own expense, as of the Closing Date, the MERS ^® System to indicate that such Mortgage Loans have been assigned by the Seller to the Trustee in accordance with this Agreement for the benefit of the Certificateholders by including (or deleting, in the case of Mortgage Loans which are repurchased in accordance with the Pooling and Servicing Agreement) in such computer files (a) the code in the field which identifies the specific Trustee and (b) the code in the field “Pool Field” which identifies the series of the Certificates issued in connection with such Mortgage Loans.

Notwithstanding anything to the contrary contained in this Section 2.1, in those instances where the public recording office retains the original Mortgage after it has been recorded, the Seller shall be deemed to have satisfied its obligations hereunder upon delivery to the Trustee of a copy of such Mortgage certified by the public recording office to be a true and complete copy of the recorded original thereof.

If any Assignment is lost or returned unrecorded to the Trustee because of any defect therein, the Seller shall prepare a substitute Assignment or cure such defect, as the case may be, and the Seller shall cause such Assignment to be recorded in accordance with this section.

The Seller shall exercise its best reasonable efforts to deliver or cause to be delivered to the Trustee within 120 days of the Closing Date the original or a photocopy of the title insurance policy with respect to each Mortgage Loan assigned to the Trustee pursuant to this Section 2.1.

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If a material defect in any Mortgage File is discovered which may materially and adversely affect the value of the related Mortgage Loan, or the interests of the Certificateholders or the Certificate Insurer in such Mortgage Loan including if any document required to be delivered to the Trustee has not been delivered (provided that a Mortgage File will not be deemed to contain a defect for an unrecorded assignment under clause (iii) above if the Seller has submitted such assignment for recording pursuant to the terms of the following paragraph), the Seller shall either (i) purchase such Mortgage Loan from the Trust Fund at the Purchase Price within 90 days after the date on which the Seller was notified of such defect; provided, that if such defect would cause the Mortgage Loan to be other than a “qualified mortgage” as defined in Section 860G(a)(3) of the Code, any such cure or repurchase must occur within 90 days from the date such breach was discovered, or cure such defect, or (ii) substitute a Qualified Substitute Mortgage Loan for the related Mortgage Loan upon the same terms and conditions set forth in Section 3.1 hereof for substitutions.

The Purchaser hereby acknowledges its acceptance of all right, title and interest to the Mortgage Loans and other property, now existing and hereafter created, conveyed to it pursuant to this Section 2.1, other than with respect to servicing rights with respect to the Mortgage Loans.

(c) The parties hereto intend that the transaction set forth herein constitutes a sale by the Seller to the Purchaser of all the Seller’s right, title and interest in and to the Mortgage Loans (other than with respect to the related servicing rights) and other property as and to the extent described above. In the event the transaction set forth herein is deemed not to be a sale, the Seller hereby grants to the Purchaser a security interest in all of the Seller’s right, title and interest in, to and under the Mortgage Loans (other than with respect to the related servicing rights) and such other property, to secure all of the Seller’s obligations hereunder, and this Agreement shall constitute a security agreement under applicable law. The Seller agrees to take or cause to be taken such actions and to execute such documents, including without limitation the filing of all necessary UCC-1 financing statements filed in the State of California (which shall have been submitted for filing as of the Closing Date with respect to the aggregate Stated Principal Balance of the Mortgage Loans), any continuation statements with respect thereto and any amendments thereto required to reflect a change in the name or corporate structure of the Seller or the filing of any additional UCC-1 financing statements due to the change in the principal office of the Seller, as are necessary to perfect and protect the Purchaser’s interests in each Mortgage Loan and the proceeds thereof.

Section 2.2 Payment of Purchase Price for the Mortgage Loans .

(a) The purchase price for the Mortgage Loans (other than with respect to the servicing rights thereto) shall be the sum of (1) $ [              ] and (2) a 100% Percentage Interest in the Class 1-B, Class 1-C, Class 1-P, Class 2-C, Class 2-P and Class R Certificates.

(b) In consideration of the sale of the Mortgage Loans from the Seller to the Purchaser on the Closing Date, the Purchaser shall pay to the Seller on the Closing Date by wire transfer of immediately available funds to a bank account designated by the Seller, the amount specified above in clause (a)(1).

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ARTICLE III

REPRESENTATIONS AND WARRANTIES;

REMEDIES FOR BREACH

Section 3.1 Seller Representations and Warranties . The Seller hereby represents and warrants to the Purchaser and the Certificate Insurer as of the Closing Date (or if otherwise specified below, as of the date so specified) that:

(a) with respect to the Seller:

(i) the Seller is a corporation duly organized, validly existing and in good standing under the laws of the State of California;

(ii) the Seller has full corporate power to own its property, to carry on its business as presently conducted and to enter into and perform its obligations under this Agreement;

(iii) the execution and delivery by the Seller of this Agreement have been duly authorized by all necessary corporate action on the part of the Seller; and neither the execution and delivery of this Agreement, nor the consummation of the transactions herein contemplated hereby, nor compliance with the provisions hereof, will conflict with or result in a breach of, or constitute a default under, any of the provisions of any law, governmental rule, regulation, judgment, decree or order binding on the Seller or its properties or the certificate of incorporation or by-laws of the Seller, except those conflicts, breaches or defaults which would not reasonably be expected to have a material adverse effect on the Seller’s ability to enter into this Agreement and to consummate the transactions contemplated hereby;

(iv) the execution, delivery and performance by the Seller of this Agreement and the consummation of the transactions contemplated hereby do not require the consent or approval of, the giving of notice to, the registration with, or the taking of any other action in respect of, any state, federal or other governmental authority or agency, except those consents, approvals, notices, registrations or other actions as have already been obtained, given or made and, in connection with the recordation of the Mortgages, powers of attorney or assignments of Mortgages not yet completed;

(v) this Agreement has been duly executed and delivered by the Seller and, assuming due authorization, execution and delivery by the Purchaser, constitutes a valid and binding obligation of the Seller enforceable against it in accordance with its terms (subject to applicable bankruptcy and insolvency laws and other similar laws affecting the enforcement of the rights of creditors generally);

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(vi) to the knowledge of the Seller, there are no actions, litigation, suits or proceedings pending or threatened against the Seller before or by any court, administrative agency, arbitrator or governmental body (i) with respect to any of the transactions contemplated by this Agreement or (ii) with respect to any other matter which in the judgment of the Seller if determined adversely to the Seller would reasonably be expected to materially and adversely affect the Seller’s ability to perform its obligations under this Agreement; and the Seller is not in default with respect to any order of any court, administrative agency, arbitrator or governmental body so as to materially and adversely affect the transactions contemplated by this Agreement; and

(vii) the Seller’s chief executive office and principal place of business are located in the County of Orange in the State of California; and

(b) with respect to the Mortgage Loans:

(i) the information with respect to each Mortgage Loan set forth in the Mortgage Loan Schedule is true and correct as of the Cut-Off Date, based on Cut-Off Date Balances;

(ii) each Mortgage Loan is being serviced either (i) through the Servicer or (ii) a Person controlling, controlled by or under common control with the Servicer and qualified to service mortgage loans;

(iii) each Mortgage Loan was underwritten or reunderwritten pursuant to the underwriting guidelines which conform in all material respects to the description thereof set forth in the Prospectus Supplement;

(iv) all of the original or certified documentation required to be delivered to the Trustee pursuant to this Agreement (including all material documents related thereto) with respect to each Mortgage Loan has been or will be delivered to the Trustee in accordance with the terms of this Agreement. Each of the documents and instruments specified to be included therein has been duly executed and in due and proper form, and each such document or instrument is in a form generally acceptable to prudent mortgage lenders that regularly originate or purchase mortgage loans comparable to the Mortgage Loans for sale to prudent investors in the secondary market that invest in mortgage loans such as the Mortgage Loans;

(v) each Mortgaged Property is improved by a single (one to four) family residential dwelling, which may include condominiums, individual units in a planned unit development and townhouses but shall not include cooperatives;

(vi) no Mortgage Loan had a Loan-to-Value Ratio at origination in excess of 100%;

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(vii) each Mortgage Loan is a valid, subsisting enforceable and perfected first lien as identified on the Mortgage Loan Schedule on the Mortgaged Property and subject in all cases to the exceptions to title set forth in the title insurance policy, with respect to the related Mortgage Loan, which exceptions are generally acceptable to banking institutions in connection with their regular mortgage lending activities, and such other exceptions to which similar properties are commonly subject and which do not individually, or in the aggregate, materially and adversely affect the benefits of the security intended to be provided by such Mortgage. At the time each Mortgage Loan was originated, the originator was a mortgagee approved by the Secretary of Housing and Urban Development pursuant to Sections 203 and 211 of the National Housing Act or a savings and loan association, a savings bank, a commercial bank or similar banking institution which was supervised and examined by a federal or state authority or a mortgage banker or broker licensed or authorized to do business in the jurisdiction in which the related Mortgaged Property is located, applying the same standards and procedures used by the Sponsor in originating Mortgage Loans directly;

(viii) immediately prior to the transfer and assignment of the Mortgage Loans to the Depositor, the Sponsor held good and marketable title to, and was the sole owner of each Mortgage Loan, subject to no liens, charges, mortgages or encumbrances or rights of others, except liens of third party warehouse lenders that will be released simultaneously with the transfer and assignment contemplated herein; and immediately prior to the transfer and assignment herein contemplated, the Depositor held good and marketable title to, and was the sole owner of, each Mortgage Loan subject to no liens, charges, mortgages, encumbrances or rights of others except liens which will be released simultaneously with such transfer and assignment; and immediately upon the transfer and assignment herein contemplated, the Trustee will hold good and marketable title to, and be the sole owner of, each Mortgage Loan subject to no liens, charges, mortgages, encumbrances or rights of others except liens which will be released simultaneously with such transfer and assignment;

(ix) there is no delinquent tax or assessment lien on any Mortgaged Property, and each Mortgaged Property is free of substantial damage and is in good repair;

(x) there is no valid and enforceable right of rescission, set-off, defense or counterclaim to any Mortgage Note or Mortgage, including the obligation of the related Mortgagor to pay the unpaid principal of or interest on such Mortgage Note or the defense of usury, nor will the operation of any of the terms of the Mortgage Note or the Mortgage, or the exercise of any right thereunder, render either the Mortgage Note or the Mortgage unenforceable in whole or in part, or subject to any right of rescission, set-off, counterclaim or defense, including the defense of usury, and no such right of rescission, set-off, counterclaim or defense has been asserted with respect thereto;

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(xi) there is no mechanics’ lien or claim for work, labor or material affecting any Mortgaged Property which is or may be a lien prior to, or equal with and no rights are outstanding that under the law gives rise to such liens, the lien of the related Mortgage except those which are insured against by any title insurance policy referred to in paragraph (xiii) below;

(xii) each Mortgage Loan at the time it was made complied with, and each Mortgage Loan at all times was serviced in compliance with, in each case, in all material respects, applicable local, state and federal laws and regulations, including, without limitation, the federal Truth-in-Lending Act and other consumer protection laws, the Home Ownership and Equity Protection Act of 1994, real estate settlement procedure, usury, equal credit opportunity, disclosure and recording laws and all applicable predatory and abusive lending laws;

(xiii) with respect to each Mortgage Loan, a lender’s title insurance policy, issued in standard California Land Title Association form or American Land Title Association form, or other form acceptable in a particular jurisdiction by a title insurance company authorized to transact business in the state in which the related Mortgaged Property is situated, in an amount at least equal to the original principal balance of such Mortgage Loan insuring the mortgagee’s interest under the related Mortgage Loan as the holder of a valid first mortgage lien of record on the real property described in the related Mortgage, as the case may be, subject only to exceptions of the character referred to in paragraph (vii) above, was effective on the date of the origination of such Mortgage Loan, and, as of the Closing Date such policy will be valid and inure to the benefit of the Trustee on behalf of the Certificateholders;

(xiv) the improvements upon each Mortgaged Property are covered by a valid and existing hazard insurance policy (which may be a blanket policy of the type described in this Agreement) with a generally acceptable carrier that provides for fire and extended coverage representing coverage not less than the least of (i) the outstanding principal balance of the related Mortgage Loan, (ii) the minimum amount required to compensate for damage or loss on a replacement cost basis or (iii) the full insurable value of the Mortgaged Property;

(xv) if any Mortgaged Property is in an area identified in the Federal Register by the Federal Emergency Management Agency as having special flood hazards, a flood insurance policy (which may be a blanket policy of the type described in this Agreement) in a form meeting the requirements of the current guidelines of the Federal Insurance Administration is in effect with respect to such Mortgaged Property with a generally acceptable carrier in an amount representing coverage not less than the least of (i) the outstanding Principal Balance of the related Mortgage Loan (together, in the case of a second mortgage loan, with the outstanding principal balance of the first mortgage loan), (ii) the minimum amount required to compensate for damage or loss on a replacement cost basis or (iii) the maximum amount of insurance that is available under the Flood Disaster Protection Act of 1973;

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(xvi) each Mortgage and Mortgage Note is the legal, valid and binding obligation of the maker thereof and is enforceable in accordance with its terms, except only as such enforcement may be limited by bankruptcy, insolvency, reorganization, moratorium or other similar laws affecting the enforcement of creditors’ rights generally and by general principles of equity (whether considered in a proceeding or action in equity or at law), and all parties to each Mortgage Loan had full legal capacity to execute all documents relating to such Mortgage Loan and convey the estate therein purported to be conveyed;

(xvii) the Sponsor has directed and the Depositor has caused to be performed any and all acts required to be performed to preserve the rights and remedies of the Trustee in any Insurance Policies applicable to any Mortgage Loan delivered by the Sponsor or the Depositor including, to the extent such Mortgage Loan is not covered by a blanket policy described in this Agreement, any necessary notifications of insurers, assignments of policies or interests therein, and establishments of coinsured, joint loss payee and mortgagee rights in favor of the Trustee;

(xviii) the Sponsor has caused or will have caused, within ten days, the filing of all appropriate financing statements in the proper filing office in the appropriate jurisdictions under applicable law in order to perfect the security interest in the original Mortgage Note and all subsequent assignments of the original Mortgage, granted to the Trustee hereunder, subject to the provisions of this Agreement and the Pooling and Servicing Agreement;

(xix) the terms of each Mortgage Note and each Mortgage have not been impaired, altered, waived or modified in any respect, except by a written instrument which has been recorded, if necessary, to protect the interest of the Certificateholders and which has been delivered to the Trustee;

(xx) the proceeds of each Mortgage Loan have been fully disbursed, there is no obligation on the part of the mortgagee to make future advances thereunder and all costs, fees and expenses incurred in making or closing or recording such Mortgage Loans were paid;

(xxi) except as otherwise required by law or pursuant to the statute under which the related Mortgage Loan was made, the related Mortgage Note is not and has not been secured by any collateral, pledged account or other security except the lien of the corresponding Mortgage;

(xxii) no Mortgage Loan was originated under a buydown plan;

(xxiii) no Mortgage Loan provides for negative amortization, has a shared appreciation feature, or other contingent interest feature;

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(xxiv) each Mortgaged Property is located in the state identified in the Mortgage Loan Schedule and consists of one or more parcel