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                                                                   EXHIBIT 10.23

                             SUPPLEMENTAL AGREEMENT
                        TO MASTER SUB-SERVICING AGREEMENT


        This agreement, dated as of September 1, 1998, is a Supplement
("Supplement") to that certain Master Sub-Servicing Agreement ("Sub-Servicing
Agreement") dated as of April 28, 1997, and is entered into with reference to
the following facts:

        A. Ameriquest Mortgage Company, ("AMC" or "Subservicer"), formerly known
as Long Beach Mortgage Company, and Long Beach Mortgage Company ("LBMC" or
"Master Servicer") formerly known as Ameriquest Mortgage Corporation, entered
into the Sub-Servicing Agreement pursuant to which AMC agreed to act as
subservicer for certain Mortgage Loans originated by LBMC and for which LBMC
acts as master servicer.

        B. AMC and LBMC now desire to modify and supplement certain terms and
conditions of the Sub-Servicing Agreement as set forth in this Supplement.

        In reliance on the foregoing facts, and in consideration of the mutual
covenants and agreements contained in this Supplement, LBMC and AMC have agreed
as follows:

        1. Use of Defined Terms. Unless specifically defined in the body of this
Supplement, or the context otherwise requires, all capitalized terms used in
this Supplement shall have the meanings ascribed to them in the Sub-Servicing
Agreement.

        2. Transfer of Mortgage Loan Servicing. Prior to the date of this
Supplement LBMC has transferred the servicing of certain Mortgage Loans that had
been delivered to AMC for servicing pursuant to the terms of the Sub-Servicing
Agreement. These prior servicing transfers are hereby ratified and confirmed.
AMC and LBMC further agree that the servicing for any of the following Mortgage
Loans (including any Mortgaged Property acquired in connection with the
foreclosure or deed in lieu of foreclosure of any Mortgage Loan) may also be
transferred by LBMC to itself or another servicer in accordance with the
provisions of subsections 2.1 through 2.4 below:

               (i) Mortgage Loans are owned by LBMC to Lehman Brothers (or its
                   affiliates) on a servicing released basis;

               (ii) Mortgage Loans that have been sold by LBMC to Credit Suisse
                    First Boston Mortgage Capital, LLC (or its affiliates); and

               (iii) Mortgage Loans that are owned by LBMC on or after the date
                     of this Supplement.

               2.1 Notice. The Master Servicer shall have provided the
Subservicer written notice of the Master Servicer's intention to transfer
servicing of Mortgage Loans as provided for in this Section 2 at least 25 days
prior to the proposed transfer of such Mortgage Loans. Such notice shall
identify with specificity the loans to be transferred and the date of transfer.

               2.2 Consents. The Master Servicer shall have provided to the
Subservicer copies of any consents or approvals required by investors,
regulatory bodies, credit insurers, Rating Agencies and any other parties which
may have the right to object to the transfer of the servicing or subservicing
rights to any Mortgage Loan.

               2.3 Payment of Accrued Fees. Prior to the transfer of any
servicing hereunder, the Subservicer shall receive (i) reimbursement for any
Servicing Advance or P & I Advance which it may have made in connection with the
Mortgage Loans to be transferred, regardless of the timing for such


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reimbursement as provided for in the Sub-Servicing Agreement; and (ii) a
servicing release fee in an amount equal to $25.00 for each Mortgage Loan
transferred. In addition, if the date of transfer is after November 1, 1998,
LBMC shall pay to AMC all unpaid Servicing Fees accruing after November 1, 1998.
AMC shall earn a full month's servicing fee for any partial month of servicing
after November 1, 1998; provided, however, if the servicing transfer date is on
the first or second business day of any month, no servicing fee shall be due for
the one or two business days of servicing during which no servicing activities
by AMC will be required.

               2.4 Goodbye Letters. The Subservicer shall provide, or cause to
be provided, a "good-bye" notice to the related borrowers regarding the transfer
of the servicing as well as any notices required to be given to insurance
carriers and tax services.

        3. Payment of Unpaid Servicing Fees. Concurrently with the execution of
this Supplement, the Master Servicer shall pay, and the Subservicer shall
accept, the sum of $200,000.00 as payment in full and complete satisfaction of
all unpaid Servicing Fees accrued or yet to accrue through November 1, 1998 with
respect to Mortgage Loans for which the servicing was or is to be transferred by
the Master Servicer prior to November 1, 1998. Notwithstanding the foregoing,
the Subservicer shall continue to earn and shall retain the Sub-Servicing Fee
related to each Mortgage Loan from payments of interest collected by the
Subservicer with respect to such loan.

        4. Termination of Sub-Servicing Agreement. Effective as of November 1,
1998 ("Acceptance Termination Date") the Subservicer shall have no obligation to
accept for subservicing any Mortgage Loans originated, purchased or otherwise
acquired by the Master Servicer, except as otherwise agreed to pursuant to the
terms of the Standby Servicing Agreement between the parties dated as of
September 1, 1998. Neither shall the Master Servicer have any right or
obligation to submit any Mortgage Loan to the Subservicer for subservicing from
or after the Acceptance Termination Date.

        5. Amendment to Sub-Servicing Agreement. Pursuant to the provisions of
Section 7.01 of the Sub-Servicing Agreement, this Supplement is intended to be
an amendment to the Sub-Servicing Agreement, such that, in the event of any
conflict between the provisions of this Supplement and those of the
Sub-Servicing Agreement, the provisions of this Supplement shall prevail.
Otherwise, unless specifically modified, amended or deleted by this Supplement,
the provisions of the Sub-Servicing Agreement shall remain in full force and
effect. Nothing in this Supplement is intended to amend or modify in any way
Section 5.04 of the Sub-Servicing Agreement, including, without limitation,
either party's right to terminate such agreement.

        IN WITNESS WHEREOF, the parties have executed this Sub-Servicing
Agreement as of the 1st day of September, 1998.

    LONG BEACH MORTGAGE COMPANY              AMERIQUEST MORTGAGE COMPANY



By: /s/ M. JACK MAYESH                       By:  /s/ NORMAN R. GRITSCH
    -------------------------------               -----------------------------
    M. Jack Mayesh,                               Norman R. Gritsch,
    Chief Executive Officer                       Executive Vice President and
                                                  General Counsel




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