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                                                                    EXHIBIT 10.1

Ambac                                          Ambac Assurance Corporation
CERTIFICATE GUARANTY INSURANCE POLICY          c/o CT Corporation Systems
                                               44 East Mifflin Street, Madison,
                                                  Wisconsin 53703
                                               Administrative Office
                                               One State Street Plaza, New York,
                                                  New York 10004
                                               Telephone:  (212) 668-0340

Insured Obligations:                           Policy Number:
ABFS Mortgage Loan Trust 2000-4                AB0422BE

Mortgage-Backed Notes, Series 2000-4

                                               Premium:

                                               As specified in the endorsement
                                               attached hereto.

AMBAC ASSURANCE CORPORATION (Ambac) A Wisconsin Stock Insurance Company in
consideration of the payment of the premium and subject to the terms of this
Policy, hereby agrees unconditionally and irrevocably to pay to the Trustee for
the benefit of the Holders of the Insured Obligations, that portion of the
Insured Amounts which shall become Due for Payment but shall be unpaid by reason
of Nonpayment.

Ambac will make such payments to the Trustee from its own funds on the later of
(a) one (1) Business Day following notification to Ambac of Nonpayment or (b)
the Business Day on which the Insured Amounts are Due for Payment. Such payments
of principal or interest shall be made only upon presentation of an instrument
of assignment in form and substance satisfactory to Ambac, transferring to Ambac
all rights under such Insured Obligations to receive the principal of and
interest on the Insured Obligation. Ambac shall be subrogated to all the
Holders' rights to payment on the Insured Obligations to the extent of the
insurance disbursements so made. Once payments of the Insured Amounts have been
made to the Trustee, Ambac shall have no further obligation hereunder in respect
of such Insured Amounts.

In the event the Trustee for the Insured Obligations has notice that any payment
of principal or interest on an Insured Obligation which has become Due for
Payment and which is made to a Holder by or on behalf of the Trustee has been
deemed a preferential transfer and theretofore recovered from its Holder
pursuant to the United States Bankruptcy Code in accordance with a final,
nonappealable order of a court of competent jurisdiction, such Holder will be
entitled to payment from Ambac to the extent of such recovery if sufficient
funds are not otherwise available.

This Policy is noncancelable by Ambac for any reason, including failure to
receive payment of any premium due hereunder. The premium on this Policy is not
refundable for any reason. This Policy does not insure against loss of any
prepayment or other acceleration payment which at any time may become due in
respect of any Insured Obligation, other than at the sole option of Ambac, nor
against any risk other than Nonpayment, including failure of the Trustee to make
any payment due Holders of Insured Amounts.

To the fullest extent permitted by applicable law, Ambac hereby waives and
agrees not to assert any and all tights and defenses, to the extent such rights
and defenses may be available to Ambac, to avoid payment of its obligations
under this Policy in accordance with the express provisions hereof.

Any capitalized terms not defined herein shall have the meaning given such terms
in the endorsement attached hereto or in the Agreement.

In witness whereof, Ambac has caused this Policy to be affixed with its
corporate seal and to be signed by its duly authorized officers in facsimile to
become effective as their original signatures and binding upon Ambac by virtue
of the countersignature of its duly authorized representative.

President                                              Secretary

Effective Date:  December 21, 2000                     Authorized Representative

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                CERTIFICATE GUARANTY INSURANCE POLICY ENDORSEMENT

Attached to and forming part of                   Effective Date of Endorsement:
Certificate Guaranty Insurance Policy #AB0422BE                December 21, 2000

issued to:

The Chase Manhattan Bank,
as Indenture Trustee for the Holders of
ABFS Mortgage Loan Trust 2000-4,
Mortgage-Backed Notes, Series 2000-4

         For all purposes of this Policy, the following terms shall have the
following meanings:

         "Agreement" shall mean the Sale and Servicing Agreement, dated as of
December 1, 2000, among Bear Stearns Asset-Backed Securities, Inc., as
Depositor, ABFS Mortgage Loan Trust 2000-4, as Issuer, American Business Credit,
Inc., as Servicer and The Chase Manhattan Bank, as Indenture Trustee and
Collateral Agent.

         "Deficiency Amount" means, for each Payment Date, the excess, if any,
of Required Distributions over the Net Available Funds.

         "Due for Payment" shall mean with respect to any Insured Payment or
Preference Amount, such amount is due and payable pursuant to the terms of the
Indenture.

         "First Payment Date" shall mean January 16, 2001.

         "Holder" shall mean the registered owner or beneficial owner of any
Note.

         "Indenture" shall mean the Indenture dated as of December 1, 2000
between ABFS Mortgage Loan Trust 2000-4, as Issuer and The Chase Manhattan Bank,
as Indenture Trustee, as such agreement may be amended, modified or supplemented
from time to time as set forth in the Indenture.

         "Indenture Trustee" or "Trustee" shall mean The Chase Manhattan Bank,
in its capacity as Indenture Trustee under the Indenture, or if any successor
Indenture Trustee or any co-trustee shall be appointed as provided therein, then
"Indenture Trustee" shall also mean such successor trustee or such co-trustee,
as the case may be, subject to the provisions thereof.

         "Insurance Agreement" shall mean the Insurance and Indemnity Agreement,
dated as of December 21, 2000, Ambac Assurance Corporation, as Note Insurer,
Bear Stearns Asset-Backed Securities, Inc., as Depositor, ABFS Mortgage Loan
Trust 2000-4, as Issuer, American Business Credit, Inc., as Servicer and
Originator, HomeAmerican Credit, Inc. d/b/a Upland Mortgage, as Originator, New
Jersey Mortgage and Investment Corp., as Originator, ABFS 2000-4,

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Inc., as Seller and The Chase Manhattan Bank, as Indenture Trustee, as such
agreement may be amended, modified or supplemented from time to time.

         "Insured Amounts" shall mean, with respect to any Payment Date, any
Deficiency Amount for such Payment Date.

         "Insured Payments" shall mean, with respect to any Payment Date, the
aggregate amount paid by the Note Insurer to the Indenture Trustee in respect of
(i) Insured Amounts for such Payment Date and (ii) Preference Amounts for any
given Business Day.

         "Late Payment Rate" shall mean for any Payment Date, the greater of (i)
the rate of interest, as it is publicly announced by Citibank, N.A. at its
principal office in New York, New York as its prime rate (any change in such
prime rate of interest to be effective on the date such change is announced by
Citibank, N.A.) plus 2% and (ii) the then applicable highest rate of interest on
the Notes. The Late Payment Rate shall be computed on the basis of a year of 360
days and the actual number of days elapsed. In no event shall the Late Payment
Rate exceed the maximum rate permissible under any applicable law limiting
interest rates.

         "Net Available Funds" on any Payment Date means the Available Funds on
deposit in the Payment Account on such Payment Date, less the Indenture
Trustee's Fee and the Premium.

         "Nonpayment" shall mean, with respect to any Payment Date, an Insured
Amount is Due for Payment but has not been paid pursuant to the Agreement.

         "Note Insurer" means Ambac Assurance Corporation, a Wisconsin-domiciled
stock insurance corporation, or any successor thereto, as issuer of the Policy.

         "Notes" means the Class A Notes, substantially in the form set forth in
Exhibit A to the Indenture.

         "Notice" shall mean the telephonic or telegraphic notice, promptly
confirmed in writing by telecopy substantially in the form of Exhibit A to the
Policy, the original of which is subsequently delivered by registered or
certified mail, from the Indenture Trustee specifying the Insured Amount which
shall be due and owing on the applicable Payment Date.

         "Payment Account" shall have the meaning set forth in Appendix A to the
Indenture.

         "Payment Date" shall mean the 15th day of any month (or if such 15th
day is not a Business Day, the first Business Day immediately following)
beginning on the First Payment Date.

         "Policy" shall mean this Certificate Guaranty Insurance Policy together
with each and every endorsement hereto.

         "Preference Amount" means any payment of principal or interest on a
Note which has become Due for Payment and which is made to a Holder by or on
behalf of the Indenture Trustee which has been deemed a preferential transfer
and theretofore recovered from its Holder pursuant to the United States
Bankruptcy Code in accordance with a final, nonappealable order of a court of
competent jurisdiction.

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         "Premium" shall mean the amount payable to the Note Insurer on each
Payment Date calculated at the Premium Percentage.

         "Premium Percentage" shall have the meaning set forth in the Insurance
Agreement.

         "Reimbursement Amount" shall mean, as to any Payment Date, the sum of
(x) (i) all Insured Payments paid by the Note Insurer, but for which the Note
Insurer has not been reimbursed prior to such Payment Date pursuant to Section
8.02(v) of the Indenture, plus (ii) interest accrued on such Insured Payments
not previously repaid calculated at the Late Payment Rate from the date the
Indenture Trustee received the related Insured Payments or the date such Insured
Payments were made, and (y) without duplication (i) any amounts then due and
owing to the Note Insurer under the Insurance Agreement, as certified to the
Indenture Trustee by the Note Insurer plus (ii) interest on such amounts at the
Late Payment Rate.

         "Required Distributions" shall mean (i) with respect to any Payment
Date occurring prior to the Payment Date in December 2031, (x) the Interest
Payment Amount; and (y) any Overcollateralization Deficit after application of
Available Funds; and (ii) with respect to the Final Stated Maturity Date, the
aggregate Outstanding Note Principal Balance, after giving effect to all other
payments of principal on the Notes on that Payment Date.

         Capitalized terms used herein as defined terms and not otherwise
defined herein shall have the meaning assigned to them in the Insurance
Agreement, the Sale and Servicing Agreement and the Indenture.

         Notwithstanding any other provision of the Policy, the Note Insurer
will pay any amount payable hereunder no later than 12:00 noon, New York City
time, on the later of (i) the Payment Date on which the related Insured Amount
is due and (ii) the Business Day following receipt in New York, New York on a
Business Day by the Note Insurer of a Notice at the address and in the manner
provided in Section 6.02 of the Insurance Agreement; provided that, if such
Notice is received after 12:00 noon, New York City time, on such Business Day,
it shall be deemed to be received on the following Business Day. If any such
Notice is not in proper form or is otherwise insufficient for the purpose of
making a claim under the Policy, it shall be deemed not to have been received
for purposes of this paragraph, and the Note Insurer shall promptly so advise
the Indenture Trustee and the Indenture Trustee may submit an amended or
corrected Notice.

         As provided in the third paragraph of the Policy, the Note Insurer
shall pay any Preference Amount when due to be paid pursuant to the Order
referred to below, but in any event no earlier than the third Business Day
following receipt by the Note Insurer of (i) a certified copy of a final,
nonappealable order of a court or other body exercising jurisdiction in such
insolvency proceeding to the effect that the Indenture Trustee, or Holder, as
applicable, is required to return such Preference Amount paid during the term of
this Policy because such payments were avoided as a preferential transfer or
otherwise rescinded or required to be restored by the Indenture Trustee or
Holder (the "Order"), (ii) a certificate by or on behalf of the Indenture
Trustee or Holder that the Order has been entered and is not subject to any
stay, (iii) an assignment, in form and substance satisfactory to the Note
Insurer, duly executed and delivered by the Indenture Trustee or Holder,
irrevocably assigning to the Note Insurer all rights and claims of the Indenture
Trustee or Holder relating to or arising under the Indenture against the estate
of the Indenture Trustee or otherwise

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with respect to such Preference Amount and (iv) a Notice of Nonpayment (in the
form attached hereto as Exhibit A) appropriately completed and executed by the
Indenture Trustee. Such payment shall be disbursed to the receiver, conservator,
debtor-in-possession or trustee in bankruptcy named in the Order, and not to the
Holder directly, unless the Holder has made a payment of the Preference Amount
to the court or such receiver, conservator, debtor-in-possession or trustee in
bankruptcy named in the Order, in which case the Note Insurer will pay the
Holder, subject to the delivery of (a) the items referred to in clauses (i),
(ii), (iii) and (iv) above to the Note Insurer and (b) evidence satisfactory to
the Note Insurer that payment has been made to such court or receiver,
conservator, debtor-in-possession or trustee in bankruptcy named in the Order.

         The Note Insurer hereby agrees that if it shall be subrogated to the
rights of Holders by virtue of any previous payment under this Policy, no
recovery of such payment will occur unless the full amount of the Holders'
allocable distributions for such Payment Date can be made. In so doing, the Note
Insurer does not waive its rights to seek full payment of all Reimbursement
Amounts owed to it under the Agreement.

         The terms and provisions of the Agreement constitute the instrument of
assignment referred to in the second paragraph of the face of this Policy.

         A premium will be payable on this Policy on each Payment Date as
provided in Section 8.02(ii) of the Indenture, beginning with the first Payment
Date, in an amount equal to the Premium.

         THE INSURANCE PROVIDED BY THE POLICY IS NOT COVERED BY THE
PROPERTY/CASUALTY INSURANCE SECURITY FUND SPECIFIED IN ARTICLE 76 OF THE NEW
YORK INSURANCE LAW.

         The Policy to which this Endorsement is attached and of which it forms
a part is hereby amended to provide that there shall be no acceleration payment
due under the Policy unless such acceleration is at the sole option of the Note
Insurer.

         Nothing herein contained shall be held to vary, alter, waive or extend
any of the terms, conditions, provisions, agreements or limitations of the above
mentioned Policy other than as above stated.

         To the extent the provisions of this Endorsement conflict with the
provisions in the above-mentioned Policy, the provisions of this Endorsement
shall govern.

         This Policy and the obligations of the Note Insurer hereunder shall
terminate one year and one day from the earlier to occur of: (a) the date on
which all amounts required to be paid to Holders of the Notes have been paid in
full, and (b) the Final Stated Maturity Date. Upon termination of this Policy,
the Trustee shall forthwith deliver the original of this Policy to the Note
Insurer.

         No waiver of any rights or powers of the Note Insurer, the Holders or
the Indenture Trustee or consent by any of them shall be valid unless signed by
an authorized officer or agent thereof.

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         This Policy is issued under and pursuant to, and shall be construed in
accordance with, the laws of the State of New York.

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         IN WITNESS WHEREOF, Ambac Assurance Corporation has caused this
Endorsement to the Policy to be signed by its duly authorized officers.



---------------------------------      ---------------------------------
Assistant Secretary                    First Vice President

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                                                                    EXHIBIT 10.1

                                    EXHIBIT A

                  TO THE CERTIFICATE GUARANTY INSURANCE POLICY

                               Policy No. AB0422BE

                         NOTICE OF NONPAYMENT AND DEMAND

                         FOR PAYMENT OF INSURED AMOUNTS

                                         Date: [       ]

Ambac Assurance Corporation
One State Street Plaza
New York, New York 10004
Attention: General Counsel

         Reference is made to Certificate Guaranty Insurance Policy No. AB0422BE
(the "Policy") issued by Ambac Assurance Corporation ("Ambac"). Terms
capitalized herein and not otherwise defined shall have the meanings specified
in the Policy and the Indenture, as the case may be, unless the context
otherwise requires.

         The Indenture Trustee hereby certifies as follows:

         1.    The Indenture Trustee is the Indenture Trustee under the
               Indenture for the Holders.

         2.    The relevant Payment Date is [date].

         3.    Payment on the Notes in respect of the Payment Date is due to be
               received on _______________________ under the Indenture, in an
               amount equal to $______________

         4.    There is an Insured Amount of $______________________ in respect
               of the Notes, which amount is Due for Payment pursuant to the
               terms of the Indenture.

         5.    The Indenture Trustee has not heretofore made a demand for the
               Insured Amount in respect of the Payment Date.

         6.    The Indenture Trustee hereby requests the payment of the Insured
               Amount that is Due For Payment be made by Ambac under the Policy
               and directs that payment under the Policy be made to the
               following account by bank wire transfer of federal or other
               immediately available funds in accordance with the terms of the
               Policy to: ____________________(Indenture Trustee's account
               number).

         7.    The Indenture Trustee hereby agrees that, following receipt of
               the Insured Payment from Ambac, it shall (a) hold such amounts in
               trust and apply the

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               same directly to the distribution of payment on the Notes when
               due; (b) not apply such funds for any other purpose; (c) deposit
               such funds to the Note Account and not commingle such funds with
               other funds held by Indenture Trustee; and (d) maintain an
               accurate record of such payments with respect to each certificate
               and the corresponding claim on the Policy and proceeds thereof.

         ANY PERSON WHO KNOWINGLY AND WITH INTENT TO DEFRAUD ANY INSURANCE
COMPANY OR OTHER PERSON FILES ANAPPLICATION FOR INSURANCE OR STATEMENT OF CLAIM
CONTAINING ANY MATERIALLY FALSE INFORMATION, OR CONCEALS FOR THE PURPOSE OF
MISLEADING, INFORMATION CONCERNING ANY FACT MATERIAL THERETO, COMMITS A FRAUD
ULENT INSURANCE ACT, WHICH IS A CRIME AND SHALL ALSO BE SUBJECT TO A CIVIL
PENALTY NOT TO EXCEED FIVE THOUSAND DOLLARS AND THE STATED VAL UE OF THE CLAIM
FOR EACH SUCH VIOLATION.

                                            By:
                                                -------------------------------
                                                  Indenture Trustee

                                            Title:
                                                  -----------------------------
                                                  (Officer)

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