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                                                                   EXHIBIT 10.13

                            AMENDMENT NUMBER FIFTEEN
                                     to the
                           Master Repurchase Agreement
                            dated as of May 30, 2002
                                 by and between
              NEW CENTURY FUNDING SB-1, a Delaware statutory trust
                                       and
                      CITIGROUP GLOBAL MARKETS REALTY CORP.
                 (as successor to SALOMON BROTHERS REALTY CORP.)

     This AMENDMENT NUMBER FIFTEEN (this "Amendment Number Fifteen") is made
this 28th day of April, 2006, by and among NEW CENTURY FUNDING SB-1, a Delaware
statutory trust, having an address at c/o Christiana Bank & Trust Company, 1314
King Street, Wilmington, Delaware, 19801 ("NC SB-1") and CITIGROUP GLOBAL
MARKETS REALTY CORP. (as successor to Salomon Brothers Realty Corp.), having an
address at 390 Greenwich Street, New York, New York 10013 (the "Buyer") to the
Master Repurchase Agreement, dated as of May 30, 2002, between NC SB-1 and the
Buyer, as amended (the "Agreement").

                                    RECITALS

     WHEREAS, Buyer and NC SB-1 have agreed to amend the Agreement to extend the
termination date thereof; and

     WHEREAS, as of the date of this Amendment Number Fifteen, NC SB-1
represents to the Buyer that it is in compliance with all of the representations
and warranties and all of the affirmative and negative covenants set forth in
the Agreement and not in default under the Agreement.

     NOW THEREFORE, for good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, and of the mutual covenants herein
contained, the parties hereto hereby agree as follows:

     SECTION 1. Effective as of April 30, 2006, Section 27 of the Agreement
shall be amended by substituting "June 15, 2006" for "April 30, 2006" in clause
(i) thereof.

     SECTION 2. Representations. In order to induce the Buyer to execute and
deliver this Amendment Number Fifteen, the Seller hereby represents to the Buyer
that as of the date hereof, after giving effect to this Amendment Number
Fifteen, the Seller is in full compliance with all of the terms and conditions
of the Agreement and the Letter Agreement and no Default, Event of Default or
Material Adverse Change has occurred under the Agreement.

     SECTION 3. Fees and Expenses. Seller agrees to pay to Buyer all fees and
out of pocket expenses incurred by Buyer in connection with this Amendment
Number Fifteen and all other related documentation (including all reasonable
fees and out of

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pocket costs and expenses of Buyer's legal counsel incurred in connection with
the foregoing documents), in accordance with Section 22 of the Agreement.

     SECTION 4. Defined Terms. Any terms capitalized but not otherwise defined
herein shall have the respective meanings set forth in the Master Repurchase
Agreement.

     SECTION 5. Limited Effect. This Amendment Number Fifteen shall become
effective upon the execution hereof by the parties hereto. Except as expressly
amended and modified by this Amendment Number Fifteen, the Master Repurchase
Agreement shall continue in full force and effect in accordance with its terms.
Reference to this Amendment Number Fifteen need not be made in the Master
Repurchase Agreement or any other instrument or document executed in connection
therewith, or in any certificate, letter or communication issued or made
pursuant to, or with respect to, the Master Repurchase Agreement, any reference
in any of such items to the Master Repurchase Agreement being sufficient to
refer to the Master Repurchase Agreement as amended hereby.

     SECTION 6. GOVERNING LAW. THIS AMENDMENT NUMBER FIFTEEN 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 REGARD TO CONFLICT OF LAWS DOCTRINE APPLIED IN SUCH STATE
(OTHER THAN SECTIONS 5-1401 and 5-1402 OF THE NEW YORK GENERAL OBLIGATIONS LAW).

     SECTION 7. Counterparts. This Amendment Number Fifteen may be executed by
each of the parties hereto on any number of separate counterparts, each of which
shall be an original and all of which taken together shall constitute one and
the same instrument.

                            [Signature Page Follows]

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     IN WITNESS WHEREOF, the Buyer and the Seller have caused this Amendment
Number Fifteen to be executed and delivered by their duly authorized officers as
of the day and year first above written.

                                        NEW CENTURY FUNDING SB-1

                                        By: Christiana Bank & Trust Company, not
                                        in its individual capacity but solely as
                                        owner trustee


                                        By: /s/ James M. Young
                                            ------------------------------------
                                        Name: James M. Young
                                        Title: Assistant Vice President


                                        CITIGROUP GLOBAL MARKETS REALTY CORP.


                                        By: /s/ Bobbie Theivakumaran
                                            ------------------------------------
                                        Name: Bobbie Theivakumaran
                                        Title: Authorized Agent

     Each of the undersigned Guarantors under the Amended and Restated Guaranty
and Pledge Agreement dated as of October 1, 2004, as amended, hereby
acknowledges and agrees to the amendments and modifications to the Master
Repurchase Agreement made pursuant to this Amendment Number Fifteen.

NEW CENTURY MORTGAGE CORPORATION


By: /s/ Kevin Cloyd
    ------------------------------------
Name: Kevin Cloyd
Title: Executive Vice President


NEW CENTURY FINANCIAL CORPORATION
(f/k/a New Century REIT, Inc.)


By: /s/ Kevin Cloyd
    ------------------------------------
Name: Kevin Cloyd
Title: Executive Vice President


By: /s/ Brad A. Morrice
    ------------------------------------
Name: Brad A. Morrice
Title: Vice Chairman, President and COO