<PAGE>

                                                                  Exhibit 10.5.1





                                 AMENDMENT NO. 1
                                 ---------------


                           dated as of March 30, 2007


                                      among


                                PAGE FUNDING LLC,
                                -----------------
                            as Purchaser and Issuer,


                       CONSUMER PORTFOLIO SERVICES, INC.,
                       ----------------------------------
                             as Seller and Servicer,

                                       and

                     WELLS FARGO BANK, NATIONAL ASSOCIATION,
                     ---------------------------------------
                         as Backup Servicer and Trustee

                                     to the

             Third Amended and Restated Sale and Servicing Agreement
                          dated as of February 14, 2007

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                               AMENDMENT NO. 1 TO
             THIRD AMENDED AND RESTATED SALE AND SERVICING AGREEMENT

         AMENDMENT NO. 1, dated as of March 30, 2007 (the "AMENDMENT") by and
among PAGE FUNDING LLC, a Delaware limited liability company (in its capacities
as Purchaser, the "PURCHASER" and as Issuer, the "ISSUER," respectively),
CONSUMER PORTFOLIO SERVICES, INC., a California corporation (in its capacities
as Seller, the "SELLER" and as Servicer, the "SERVICER," respectively), WELLS
FARGO BANK, NATIONAL ASSOCIATION, a national banking association (in its
capacities as Backup Servicer, the "BACKUP SERVICER" and as Trustee, the
"TRUSTEE," respectively).

                              PRELIMINARY STATEMENT

         Reference is made to the Third Amended and Restated Sale and Servicing
Agreement dated as of February 14, 2007, among PAGE FUNDING LLC, CONSUMER
PORTFOLIO SERVICES, INC., and WELLS FARGO BANK, NATIONAL ASSOCIATION ("SALE AND
SERVICING AGREEMENT").

                                    RECITALS

         WHEREAS, PAGE FUNDING LLC, CONSUMER PORTFOLIO SERVICES, INC., and WELLS
FARGO BANK, NATIONAL ASSOCIATION (collectively, the "AMENDING PARTIES") have
executed the Sale and Servicing Agreement and the Amending Parties desire to
amend the Sale and Servicing Agreement in certain respects as provided below;
and

         WHEREAS, UBS Real Estate Securities Inc., as Controlling Note Purchaser
and Majority Noteholder of the Highest Priority Class, desires to consent to
this Amendment.



                            ARTICLE I - DEFINITIONS
                            -----------------------

         SECTION 1.1. DEFINED TERMS. Unless otherwise defined in this Amendment,
capitalized terms used in this Amendment (including in the Preamble and the
Recitals) shall have the meaning given such terms in the Annex A to the Sale and
Servicing Agreement, as identifiable from the context in which such term is
used.


                             ARTICLE II - AMENDMENT
                             ----------------------

         SECTION 2.1 AMENDMENT TO ANNEX A TO THE SALE AND SERVICING AGREEMENT.
In Annex A to the Sale and Servicing Agreement, the definition of "CLASS A
BORROWING BASE" is hereby amended and restated in its entirety to read as
follows:

          "Class A Borrowing Base" means, as of any date of determination, an
         amount equal to the sum of: (i) the CPS Borrowing Base; (ii) the lesser
         of (A) the TFC Borrowing Base and (B) $35,000,000; and (iii) Available
         Funds allocable to principal payments made by Obligors (including any
         Eligible Investments) on deposit in the Collection Account.

                                       2
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                          ARTICLE III - EFFECTIVENESS
                          ---------------------------

         SECTION 3.1. EFFECTIVE DATE. This Amendment shall be effective as of
the date of this Amendment upon execution and delivery by the parties hereto and
UBS Real Estate Securities, Inc. of this Amendment.



                           ARTICLE IV - MISCELLANEOUS
                           --------------------------

         SECTION 4.1. RATIFICATION; REPRESENTATIONS AND WARRANTIES, ETC.

     (a) Except as expressly amended hereby, all of the terms of the Basic
     Documents shall remain in full force and effect and are hereby ratified and
     confirmed in all respects. This Amendment shall not constitute a novation;

     (b) The Purchaser, Seller, Issuer and Servicer each hereby represents and
     warrants that (i) it has the requisite power and authority, and legal
     right, to execute and deliver this Amendment and to perform its obligations
     under this Amendment, the Sale and Servicing Agreement, as amended hereby,
     and the Basic Documents, (ii) it has taken all necessary corporate and
     legal action to duly authorize the execution and delivery of this Amendment
     and the performance of its obligations under this Amendment, (iii) this
     Amendment has been duly executed and delivered by it, (iv) this Amendment
     constitutes its legal, valid and binding obligation, enforceable against it
     in accordance with its terms, except as enforceability may be limited by
     applicable bankruptcy, insolvency, reorganization, moratorium or similar
     laws affecting the rights of creditors generally and by general equitable
     principles (whether enforcement is sought by proceedings in equity or at
     law), and (v), after giving effect to this Amendment, no Default or Event
     of Default has occurred and is continuing;

     (c) Each representation and warranty contained in the Basic Documents (as
     modified by this Amendment, if applicable) is true and correct and is
     hereby restated and affirmed; and

     (d) Each covenant contained in the Basic Documents (as modified by this
     Amendment, if applicable) is hereby restated and affirmed.

         SECTION 4.2. FURTHER ASSURANCES. The parties hereto hereby agree to
execute and deliver such additional documents, instruments or agreements as may
be reasonably necessary and appropriate to effectuate the purposes of this
Amendment and the other Basic Documents.

                                       3
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         SECTION 4.3. CONFLICTS. In the event of a conflict of any provision
hereof with any provision or definition set forth in the Basic Documents, the
provisions and definitions of this Amendment shall control.

         SECTION 4.4. SEVERABILITY. Any provision of this Amendment or any other
Basic Document that is prohibited, unenforceable or not authorized in any
jurisdiction shall, as to such jurisdiction, be ineffective to the extent of
such prohibition, unenforceability or non-authorization without invalidating the
remaining provisions hereof or thereof or affecting the validity, enforceability
or legality of such provisions in any other jurisdiction.

         SECTION 4.5. ENTIRE AGREEMENT. This Amendment and the other Basic
Documents constitute the entire agreement among the parties relative to the
subject matter hereof. Any previous agreement among the parties with respect to
the subject matter hereof is superseded by this Amendment and the other Basic
Documents. Nothing in this Amendment or in the other Basic Documents, expressed
or implied, is intended to confer upon any party other than the parties hereto
and thereto any rights, remedies, obligations or liabilities under or by reason
of this Amendment or the other Basic Documents.

         SECTION 4.6. BINDING EFFECT. This Amendment and the other Basic
Documents shall be binding upon and shall be enforceable by Purchaser, Seller,
Issuer, Servicer, Note Purchaser, the Backup Servicer and the Trustee and their
respective successors and permitted assigns.

         SECTION 4.7. COUNTERPARTS. This Amendment may be executed in any number
of counterparts, each of which so executed shall be deemed to be an original,
but all of such counterparts shall together constitute but one and the same
instrument.

         SECTION 4.8. GOVERNING LAW. THIS AMENDMENT AND ALL MATTERS ARISING OUT
OF OR RELATING TO THIS AMENDMENT SHALL BE GOVERNED BY AND CONSTRUED IN
ACCORDANCE WITH THE INTERNAL LAWS OF THE STATE OF NEW YORK, WITHOUT REGARD TO
CONFLICTS OF LAW PRINCIPLES.

         SECTION 4.9. HEADINGS. The headings of Sections contained in this
Amendment are provided for convenience only. They form no part of this Amendment
and shall not affect the construction or interpretation of this Amendment or any
provisions hereof.




                  [Remainder of page intentionally left blank.]

                                       4
<PAGE>


         IN WITNESS WHEREOF, the Amending Parties have caused this Amendment to
be duly executed by their respective duly authorized officers as of the day and
year first above written.

                                        PAGE FUNDING LLC, as Purchaser and as
                                                           Issuer


                                        By:  /S/ Mark Creatura
                                             -----------------------------------
                                        Title:   Vice President

                                        CONSUMER PORTFOLIO SERVICES, INC., as
                                        Seller and as Servicer


                                        By:  Robert E. Riedl
                                             -----------------------------------
                                        Title:  Sr. Vice President & CIO


                                        WELLS FARGO BANK, NATIONAL ASSOCIATION,
                                        not in its individual capacity, but
                                        solely as Backup Servicer and Trustee


                                        By:   /S/ Jason Vanvleet
                                             -----------------------------------
                                        Title:  Asst. Vice President


CONSENTED TO BY:
UBS REAL ESTATE SECURITIES, INC.,
as Controlling Note Purchaser and Majority Noteholder of the
Highest Priority Class


By:      /S/ BROCK J. WOLF
         ------------------------
Name:    BROCK J. WOLF
         ------------------------
Title:   DIRECTOR
         ------------------------



By:      /S/ PRAKASH B. WADHWANI
         ------------------------
Name:    PRAKASH B. WADHWANI
         ------------------------
Title:   EXECUTIVE DIRECTOR
         ------------------------



Signature Page to Amend. No. 1 to Third Amended and Restated Sale and Servicing
Agreement

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