Exhibit 4.2





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                         SUBSEQUENT TRANSFER INSTRUMENT

                  Pursuant to this Subsequent Transfer Instrument, dated
December 23, 2003 (the "Instrument"), between Ameriquest Mortgage Securities
Inc. as seller (the "Depositor") and Deutsche Bank National Trust Company as
trustee (the "Trustee") of the Ameriquest Mortgage Securities Inc., Asset-Backed
Pass-Through Certificates, Series 2003-13, and pursuant to the Pooling and
Servicing Agreement, dated as of December 1, 2003 (the "Pooling and Servicing
Agreement"), among the Depositor as depositor, Ameriquest Mortgage Company as
master servicer and the Trustee as trustee, the Depositor and the Trustee agree
to the sale by the Depositor and the purchase by the Trustee on behalf of the
Trust Fund, of the Mortgage Loans listed on the attached Schedule of Mortgage
Loans (the "Subsequent Mortgage Loans").

                  Capitalized terms used but not otherwise defined herein shall
have the meanings set forth in the Pooling and Servicing Agreement.

                  Section 1.        Conveyance of Subsequent Mortgage Loans.

                  (a) The Depositor does hereby sell, transfer, assign, set over
and convey to the Trustee on behalf of the Trust Fund, without recourse, all of
its right, title and interest in and to the Subsequent Mortgage Loans, and
including all amounts due on the Subsequent Mortgage Loans after the related
Subsequent Cut-off Date, and all items with respect to the Subsequent Mortgage
Loans to be delivered pursuant to Section 2.01 of the Pooling and Servicing
Agreement; provided, however that the Depositor reserves and retains all right,
title and interest in and to amounts due on the Subsequent Mortgage Loans on or
prior to the related Subsequent Cut-off Date. The Depositor, contemporaneously
with the delivery of this Agreement, has delivered or caused to be delivered to
the Trustee each item set forth in Section 2.01 of the Pooling and Servicing
Agreement. The transfer to the Trustee by the Depositor of the Subsequent
Mortgage Loans identified on the Mortgage Loan Schedule shall be absolute and is
intended by the Depositor, the Master Servicer, the Trustee and the
Certificateholders to constitute and to be treated as a sale by the Depositor to
the Trust Fund.

                  (b) The Depositor, concurrently with the execution and
delivery hereof, does hereby transfer, assign, set over and otherwise convey to
the Trustee without recourse for the benefit of the Certificateholders all the
right, title and interest of the Depositor, in, to and under the Subsequent
Mortgage Loan Purchase Agreement, dated the date hereof, between the Depositor
as purchaser and the Master Servicer as originator and as seller, to the extent
of the Subsequent Mortgage Loans.

                  (c) Additional terms of the sale are set forth on Attachment A
hereto.


         Section 2.        Representations and Warranties; Conditions Precedent.

                  (a) The Depositor hereby confirms that each of the conditions
precedent and the representations and warranties set forth in Section 2.10 of
the Pooling and Servicing Agreement are satisfied as of the date hereof.




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                  (b) All terms and conditions of the Pooling and Servicing
Agreement are hereby ratified and confirmed; provided, however, that in the
event of any conflict, the provisions of this Instrument shall control over the
conflicting provisions of the Pooling and Servicing Agreement.

                  Section 3.        Recordation of Instrument.

                  To the extent permitted by applicable law, this Instrument, or
a memorandum thereof if permitted under applicable law, is subject to
recordation in all appropriate public offices for real property records in all
of the counties or other comparable jurisdictions in which any or all of the
properties subject to the Mortgages are situated, and in any other appropriate
public recording office or elsewhere, such recordation to be effected by the
Master Servicer at the Certificateholders' expense on direction of the related
Certificateholders, but only when accompanied by an Opinion of Counsel to the
effect that such recordation materially and beneficially affects the interests
of the Certificateholders or is necessary for the administration or servicing of
the Mortgage Loans.

                  Section 4.        Governing Law.

                  This Instrument shall be construed in accordance with the laws
of the State of New York and the obligations, rights and remedies of the parties
hereunder shall be determined in accordance with such laws, without giving
effect to principles of conflicts of law.

                  Section 5.        Counterparts.

                  This Instrument may be executed in one or more counterparts
and by the different parties hereto on separate counterparts, each of which,
when so executed, shall be deemed to be an original; such counterparts,
together, shall constitute one and the same instrument.

                  Section 6.         Successors and Assigns.

                  This Instrument shall inure to the benefit of and be binding
upon the Depositor, the Trustee and their respective successors and assigns.
















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                                   AMERIQUEST MORTGAGE SECURITIES INC.


                                   By:/s/ John P. Grazer
                                      ---------------------
                                   Name: John P. Grazer
                                   Title: CFO

                                   DEUTSCHE BANK NATIONAL TRUST
                                   COMPANY, as Trustee


                                   By: /s/ Valerie Delgado
                                      ---------------------
                                   Name:   Valerie Delgado
                                   Title:  Associate


ATTACHMENTS

A. Additional terms of sale. B. Schedule of Subsequent Mortgage Loans.




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                                  ATTACHMENT A

                            ADDITIONAL TERMS OF SALE

         A.       General

                  1.   Subsequent Cut-off Date: December 1, 2003

                  2.   Subsequent Transfer Date: December 23, 2003

                  3.   Aggregate Principal Balance of the Subsequent Mortgage
                       Loans as of the Subsequent Cut-off Date:
                       $269,995,920.02

                  4.   Purchase Price: 100.00%

         B. The following representations and warranties with respect to each
Subsequent Mortgage Loan determined as of the Subsequent Cut-off Date are true
and correct: (i) the Subsequent Mortgage Loan may not be 30 or more days
delinquent as of the related Subsequent Cut-off Date; provided, however that the
Subsequent Mortgage Loans may have a first payment date occurring on or after
the Subsequent Cut-off Date and, therefore, such Subsequent Mortgage Loans could
not have been delinquent as of the Subsequent Cut-off Date; (ii) the remaining
term to stated maturity of the Subsequent Mortgage Loan will not be less than
117 months and will not exceed 360 months from its first payment date; (iii) the
Subsequent Mortgage Loan may not provide for negative amortization; (iv) the
Subsequent Mortgage Loan will not have a loan-to-value ratio greater than
95.00%; (v) the Subsequent Mortgage Loans will have, as of the related
Subsequent Cut-off Date, a weighted average age since origination not in excess
of 5 months; (vi) no Subsequent Mortgage Loan will have a Mortgage Rate less
than 5.20% or greater than 14.30%; (vii) the Subsequent Mortgage Loan will have
been serviced by the Master Servicer since origination or purchase by the
Originator in accordance with its standard servicing practices; (viii) the
Subsequent Mortgage Loan must have a first payment date occurring on or before
April 1, 2004; and (ix) the Subsequent Mortgage Loan will have been underwritten
in accordance with the criteria set forth under "--Underwriting Standards" in
the Prospectus Supplement.

         C. Following the purchase of the Subsequent Group I Mortgage Loans, the
Group I Mortgage Loans (including the related Subsequent Group I Mortgage Loans)
will, as of the related Subsequent Cut-off Date: (i) have a weighted average
original term to stated maturity of not more than 360 months from the first
payment date thereon; (ii) have a weighted average Mortgage Rate of not less
than 8.10% and not more than 8.25%; (iii) have a weighted average Loan-to-Value
Ratio of not more than 77.97%, (iv) have no Mortgage Loan with a Principal
Balance in excess of $470,742, (v) consist of Mortgage Loans with Prepayment
Charges representing no less than approximately 70.75% of the Group I Mortgage
Loans and (vi) with respect to the Adjustable-Rate Mortgage Loans in Loan Group
I, have a weighted average Gross Margin of not less than 5.97%, in each case,
measured by aggregate Principal Balance of the Group I Mortgage Loans as of the
related Cut-off Date.

         D. Following the purchase of the Subsequent Group II Mortgage Loans,
the Group II Mortgage Loans (including the related Subsequent Group II Mortgage
Loans) will, as of the related Subsequent Cut-off Date: (i) have a weighted
average original term to stated maturity of not more than 360 months from the
first payment date thereon; (ii) have a weighted average Mortgage Rate



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of not less than 7.68% and not more than 7.83%; (iii) have a weighted average
Loan-to-Value Ratio of not more than 79.55%; (iv) have no Mortgage Loan with a
Principal Balance in excess of $969,703, (v) consist of Mortgage Loans with
Prepayment Charges representing no less than approximately 61.75% of the Group
II Mortgage Loans and (vi) with respect to the Adjustable-Rate Mortgage Loans in
Loan Group II, have a Weighted Average Gross Margin of not less than 5.82%, in
each case measured by Aggregate Principal Balance of the Group II Mortgage Loans
as of the related Cut-Off Date.

         E. Following the purchase of the Subsequent Group III Mortgage Loans,
the Group III Mortgage Loans (including the related Subsequent Group III
Mortgage Loans) will, as of the related Subsequent Cut-off Date: (i) have a
weighted average original term to stated maturity of not more than 360 months
from the first payment date thereon; (ii) have a weighted average Mortgage Rate
of not less than 7.04% and not more than 7.19%; (iii) have a weighted average
Loan-to-Value Ratio of not more than 78.36%; (iv) have no Mortgage Loan with a
Principal Balance in excess of $748,349 and (v) consist of Mortgage Loans with
Prepayment Charges representing no less than approximately 78.90% of the Group
III Mortgage Loans, in each case, measured by aggregate Principal Balance of the
Group III Mortgage Loans as of the related Cut-off Date.






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                                  ATTACHMENT B

                      SCHEDULE OF SUBSEQUENT MORTGAGE LOANS

                                [FILED BY PAPER]