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                                                                   EXHIBIT 10.15

                             AMENDMENT NUMBER ELEVEN
                                     to the
                      Amended and Restated Letter Agreement
                           dated as of October 1, 2004
                                  by and among
                        NEW CENTURY MORTGAGE CORPORATION
                             NC CAPITAL CORPORATION
                         NEW CENTURY CREDIT CORPORATION
                                       and
                      CITIGROUP GLOBAL MARKETS REALTY CORP.

          This AMENDMENT NUMBER ELEVEN (this "Amendment Number Eleven") is made
this 28th day of April, 2006, among NEW CENTURY MORTGAGE CORPORATION, having an
address at 18400 Von Karman, Suite 1000, Irvine, California 92612 ("NC
Mortgage"), NC CAPITAL CORPORATION, having an address at 18400 Von Karman, Suite
1000, Irvine, California 92612 ("NC Capital"), NEW CENTURY CREDIT CORPORATION,
having an address at 18400 Von Karman, Suite 1000, Irvine, California 92612 ("NC
Credit") and CITIGROUP GLOBAL MARKETS REALTY CORP., having an address at 390
Greenwich Street, New York, New York 10013 ("Citigroup") to the Amended and
Restated Letter Agreement, dated as of October 1, 2004, among NC Mortgage, NC
Capital, NC Credit and Citigroup, as amended (the "Letter Agreement").

                                    RECITALS

          WHEREAS, NC Mortgage, NC Capital and NC Credit have requested that
Citigroup agree to extend the termination date and modify the Letter Agreement
as more expressly set forth below and Citigroup has agreed to such request.

          WHEREAS, as of the date of this Amendment Number Eleven, each of NC
Mortgage, NC Capital and NC Credit represents to Citigroup that it is in
compliance with all of the representations and warranties and all of the
affirmative and negative covenants set forth in the Letter Agreement and the
Amended and Restated Purchase and Sale Agreement, dated as of October 1, 2004,
among NC Capital, NC Credit and Citigroup (the "Purchase and Sale Agreement")
and is not in default under the Letter Agreement or the Purchase and Sale
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, the Letter Agreement is
hereby amended as follows:

          (a) The first paragraph of Section 1(a) of the Letter Agreement is
hereby amended by deleting the words "April 30, 2006" on the second and third
lines thereof and replacing each with "June 15, 2006";

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          (b) Section 2 of the Letter Agreement is hereby amended by inserting
the following new subpart at the end thereof:

               (j) NINA Loans. A "NINA Loan" is defined as any Mortgage Loan
          with respect to which the income and/or assets of the Mortgagor have
          not been fully verified prior to origination by the originator. NINA
          Loans shall be subject to the following qualifications with respect to
          the Financing Line:

                    (i) the maximum Financing Line with respect to NINA Loans
               shall equal 5% of the aggregate principal balance of all of the
               Mortgage Loans on the Financing Line at any one time.

          (c) The first paragraph of Section 4(c) of the Letter Agreement is
hereby amended by deleting the words "April 30, 2006" on the second and third
lines thereof and replacing each with "June 15, 2006".

          SECTION 2. Fees and Expenses. NC Capital agrees to pay to Citigroup
all fees and out of pocket expenses incurred by Citigroup in connection with
this Amendment Number Eleven (including all reasonable fees and out of pocket
costs and expenses of Citigroup's legal counsel incurred in connection with this
Amendment Number Eleven), in accordance with Section 5(i) of the Letter
Agreement.

          SECTION 3. Defined Terms. Any terms capitalized but not otherwise
defined herein shall have the respective meanings set forth in the Letter
Agreement.

          SECTION 4. Representations. In order to induce Citigroup to execute
and deliver this Amendment Number Eleven, NC Capital, NC Mortgage and NC Credit
hereby represent to Citigroup that as of the date hereof, after giving effect to
this Amendment Number Eleven, each of NC Capital, NC Mortgage and NC Credit is
in full compliance with all of the terms and conditions of the Letter Agreement
and the Purchase and Sale Agreement and no Termination Event or material adverse
change has occurred under the Letter Agreement and no Seller default or Seller
Event of Default has occurred under the Purchase and Sale Agreement.

          SECTION 5. Limited Effect. This Amendment Number Eleven shall become
effective upon the execution hereof by the parties hereto. Except as expressly
amended and modified by this Amendment Number Eleven, the Letter Agreement shall
continue in full force and effect in accordance with its terms. Reference to
this Amendment Number Eleven need not be made in the Letter 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 Letter Agreement, any reference in any of such items to the Letter
Agreement being sufficient to refer to the Letter Agreement as amended hereby.

          SECTION 6. GOVERNING LAW. THIS AMENDMENT NUMBER ELEVEN 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


                                      -2-

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WITHOUT REGARD TO CONFLICT OF LAWS DOCTRINE APPLIED IN SUCH STATE (OTHER THAN
SECTION 5-1401 OF THE NEW YORK GENERAL OBLIGATIONS LAW).

          SECTION 7. Counterparts. This Amendment Number Eleven 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]


                                      -3-

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          IN WITNESS WHEREOF, NC Capital, NC Mortgage, NC Credit and Citigroup
have caused this Amendment Number Eleven to be executed and delivered by their
duly authorized officers as of the day and year first above written.

                                        CITIGROUP GLOBAL MARKETS REALTY CORP.


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


                                        NC CAPITAL CORPORATION


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


                                        NEW CENTURY MORTGAGE CORPORATION


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


                                        NEW CENTURY CREDIT CORPORATION


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