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                                                                   Exhibit 10.24


                                                                     Facility II
                                                     ERT Development Corporation

                                    GUARANTY

            GUARANTY (as the same may be amended, supplemented or otherwise
modified from time to time, this "GUARANTY"), dated as of October 22, 2001, by
and between ERT DEVELOPMENT CORPORATION, a Delaware corporation (the "SUBSIDIARY
GUARANTOR"), and THE BANK OF NEW YORK, as administrative agent (in such
capacity, the "ADMINISTRATIVE AGENT") on behalf of the Lenders under and as
defined in the Credit Agreement (hereinafter defined).

                                    RECITALS

      I.    Reference is made to the Credit Agreement, dated as of November 17,
1999, by and among NEW PLAN EXCEL REALTY TRUST, INC., a Maryland corporation
(the "BORROWER"), the Lenders party thereto, the Administrative Agent, BANK ONE,
NA, as a Co-Documentation Agent, and BANKBOSTON, N.A. (n/k/a Fleet National
Bank), as a Co-Documentation Agent (as the same may be amended, supplemented or
otherwise modified from time to time, the "CREDIT AGREEMENT").

      II.   The Subsidiary Guarantor expects to derive substantial benefit from
the Credit Agreement and the transactions contemplated thereby and, in
furtherance thereof, has agreed to execute and deliver this Guaranty.

      Therefore, in consideration of the Recitals, the terms and conditions
herein contained and other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the Subsidiary Guarantor, the
Borrower and the Administrative Agent hereby agree as follows:

      1.    DEFINED TERMS

            (a)   Capitalized terms used herein which are not otherwise defined
herein shall have the respective meanings ascribed thereto in the Credit
Agreement.

            (b)   When used in this Guaranty, the following capitalized terms
shall have the respective meanings ascribed thereto as follows:

                  "BORROWER OBLIGATIONS" means all present and future
obligations and liabilities, whether deemed principal, interest, additional
interest, fees, expenses or otherwise of the Borrower to the Administrative
Agent, the Co-Documentation Agents, the Swingline Lender, the Lenders and the
Issuing Bank,
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including, without limitation, all obligations under (i) the Credit Agreement,
(ii) the Notes and (iii) all other Loan Documents.

                  "GUARANTOR OBLIGATIONS" means, with respect to the Subsidiary
Guarantor, all of the obligations and liabilities of the Subsidiary Guarantor
hereunder, whether fixed, contingent, now existing or hereafter arising,
created, assumed, incurred or acquired.

      2.    GUARANTEE

            (a)   Subject to Section 2(b), the Subsidiary Guarantor hereby
absolutely, irrevocably and unconditionally guarantees the full and prompt
payment when due (whether at stated maturity, by acceleration or otherwise) of
the Borrower Obligations. The agreements of the Subsidiary Guarantor in this
Guaranty constitute a guarantee of payment, and no Credit Party shall have any
obligation to enforce any Loan Document or exercise any right or remedy with
respect to any collateral security thereunder by any action, including making or
perfecting any claim against any Person or any collateral security for any of
the Borrower Obligations prior to being entitled to the benefits of this
Guaranty. The Administrative Agent may, at its option, proceed against the
Subsidiary Guarantor in the first instance, to enforce the Guarantor Obligations
without first proceeding against the Borrower or any other Person, and without
first resorting to any other rights or remedies, as the Administrative Agent may
deem advisable. In furtherance hereof, if any Credit Party is prevented by law
from collecting or otherwise hindered from collecting or otherwise enforcing any
Borrower Obligation in accordance with its terms, such Credit Party shall be
entitled to receive hereunder from the Subsidiary Guarantor after demand
therefor, the sums which would have been otherwise due had such collection or
enforcement not been prevented or hindered.

            (b)   Notwithstanding anything to the contrary contained herein, the
maximum aggregate amount of the obligations of the Subsidiary Guarantor
hereunder shall not, as of any date of determination, exceed the lesser of the
greatest amount that is valid and enforceable against the Subsidiary Guarantor
under principles of New York State contract law and the greatest amount that
would not render the Subsidiary Guarantor's liability hereunder subject to
avoidance as a fraudulent transfer or conveyance under Section 548 of Title 11
of the United States Code or any provisions of applicable state law
(collectively, the "FRAUDULENT TRANSFER LAWS"), in each case after giving effect
to all other liabilities of the Subsidiary Guarantor, contingent or otherwise,
that are relevant under the Fraudulent Transfer Laws (specifically excluding,
however, any liability (A) in respect of intercompany indebtedness to the
Borrower or any Affiliate or


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Subsidiary of the Borrower, to the extent that such intercompany indebtedness
would be discharged to the extent payment is made by the Subsidiary Guarantor
hereunder, and (B) under any guarantee of (1) senior unsecured indebtedness or
(2) indebtedness subordinated in right of payment to any Borrower Obligation, in
either case which contains a limitation as to maximum liability similar to that
set forth in this Section 2(b) and pursuant to which the liability of the
Subsidiary Guarantor hereunder is included in the liabilities taken into account
in determining such maximum liability) and after giving effect as assets to the
value (as determined under the applicable provisions of the Fraudulent Transfer
Laws) of any rights to subrogation, contribution, reimbursement, indemnity or
similar rights of the Subsidiary Guarantor pursuant to applicable law or any
agreement providing for an equitable allocation among the Subsidiary Guarantor
and other Affiliates or Subsidiaries of the Borrower of obligations arising
under guarantees by such parties.

            (c)   The Subsidiary Guarantor agrees that the Guarantor Obligations
may at any time and from time to time exceed the maximum aggregate amount of the
obligations of the Subsidiary Guarantor hereunder without impairing this
Guaranty or affecting the rights and remedies of any Credit Party hereunder.

      3.    ABSOLUTE OBLIGATION

            The Subsidiary Guarantor shall not be released from liability
hereunder unless and until the Commitments and Swingline Commitment have
terminated and no Letters of Credit remain outstanding and either (i) the
Borrower shall have paid in full the outstanding principal balance of the Loans,
together with all accrued and unpaid interest thereon, and all other amounts
then due and owing under the Loan Documents, or (ii) the Guarantor Obligations
of the Subsidiary Guarantor shall have been paid in full in cash. The Subsidiary
Guarantor acknowledges and agrees that (a) no Credit Party has made any
representation or warranty to the Subsidiary Guarantor with respect to the
Borrower, any of its Subsidiaries, any Loan Document, or any agreement,
instrument or document executed or delivered in connection therewith, or any
other matter whatsoever, and (b) the Subsidiary Guarantor shall be liable
hereunder, and such liability shall not be affected or impaired, irrespective of
(A) the validity or enforceability of any Loan Document, or any agreement,
instrument or document executed or delivered in connection therewith, or the
collectability of any of the Borrower Obligations, (B) the preference or
priority ranking with respect to any of the Borrower Obligations, (C) the
existence, validity, enforceability or perfection of any security interest or
collateral security under any Loan Document, or the release, exchange,
substitution or loss or


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impairment of any such security interest or collateral security, (D) any
failure, delay, neglect or omission by any Credit Party to realize upon or
protect any direct or indirect collateral security, indebtedness, liability or
obligation, any Loan Document, or any agreement, instrument or document executed
or delivered in connection therewith, or any of the Borrower Obligations, (E)
the existence or exercise of any right of set-off by any Credit Party, (F) the
existence, validity or enforceability of any other guarantee with respect to any
of the Borrower Obligations, the liability of any other Person in respect of any
of the Borrower Obligations, or the release of any such Person or any other
guarantor of any of the Borrower Obligations, (G) any act or omission of any
Credit Party in connection with the administration of any Loan Document or any
of the Borrower Obligations, (H) the bankruptcy, insolvency, reorganization or
receivership of, or any other proceeding for the relief of debtors commenced by
or against, any Person, (I) the disaffirmance or rejection, or the purported
disaffirmance or purported rejection, of any of the Borrower Obligations, any
Loan Document, or any agreement, instrument or document executed or delivered in
connection therewith, in any bankruptcy, insolvency, reorganization or
receivership, or any other proceeding for the relief of debtor, relating to any
Person, (J) any law, regulation or decree now or hereafter in effect which might
in any manner affect any of the terms or provisions of any Loan Document, or any
agreement, instrument or document executed or delivered in connection therewith
or any of the Borrower Obligations, or which might cause or permit to be invoked
any alteration in the time, amount, manner or payment or performance of any of
the Borrower's obligations and liabilities (including the Borrower Obligations),
(K) the merger or consolidation of the Borrower into or with any Person, (L) the
sale by the Borrower of all or any part of its assets, (M) the fact that at any
time and from time to time none of the Borrower Obligations may be outstanding
or owing to any Credit Party, (N) any amendment or modification of, or
supplement to, any Loan Document, or (O) any other reason or circumstance which
might otherwise constitute a defense available to or a discharge of the Borrower
in respect of its obligations or liabilities (including the Borrower
Obligations) or of the Subsidiary Guarantor in respect of any of the Guarantor
Obligations (other than by the performance in full thereof).

      4.    REPRESENTATIONS AND WARRANTIES

            The Subsidiary Guarantor represents and warrants that all
representations and warranties relating to it contained in the Credit Agreement
are true and correct.

      5.    NOTICES


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            Except as otherwise specifically provided herein, all notices,
requests, consents, demands, waivers and other communications hereunder shall be
in writing (including facsimile) and shall be given in the manner set forth in
Section 11.2 of the Credit Agreement (i) in the case of the Administrative
Agent, to the address set forth in Section 11.2 of the Credit Agreement, (ii) in
the case of the Subsidiary Guarantor, to the address set forth next to its
signature hereto, or (iii) in the case of each party hereto, to such other
addresses as to which the Administrative Agent may be hereafter notified by the
respective parties hereto.

      6.    EXPENSES

            The Subsidiary Guarantor agrees that it shall, promptly after
demand, pay to the Administrative Agent any and all reasonable out-of-pocket
sums, costs and expenses, which any Credit Party may pay or incur defending,
protecting or enforcing this Guaranty (whether suit is instituted or not),
reasonable attorneys' fees and disbursements. All sums, costs and expenses which
are due and payable pursuant to this Section shall bear interest, payable on
demand, at the highest rate then payable on the Borrower Obligations.

      7.    REPAYMENT IN BANKRUPTCY, ETC.

            If, at any time or times subsequent to the payment of all or any
part of the Borrower Obligations or the Guarantor Obligations, any Credit Party
shall be required to repay any amounts previously paid by or on behalf of the
Borrower or the Subsidiary Guarantor in reduction thereof by virtue of an order
of any court having jurisdiction in the premises, including as a result of an
adjudication that such amounts constituted preferential payments or fraudulent
conveyances, the Subsidiary Guarantor unconditionally agrees to pay to the
Administrative Agent, within 10 days after demand, a sum in cash equal to the
amount of such repayment, together with interest on such amount from the date of
such repayment by such Credit Party to the date of payment to the Administrative
Agent at the applicable after-maturity rate set forth in the Credit Agreement.

      8.    MISCELLANEOUS

            (a)   Except as otherwise expressly provided in this Guaranty, the
Subsidiary Guarantor hereby waives presentment, demand for payment, notice of
default, nonperformance and dishonor, protest and notice of protest of or in
respect of this Guaranty, the other Loan Documents and the Borrower Obligations,
notice of acceptance of this Guaranty and reliance hereupon by any


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Credit Party, and the incurrence of any of the Borrower Obligations, notice of
any sale of collateral security or any default of any sort.

            (b)   The Subsidiary Guarantor is not relying upon any Credit Party
to provide to the Subsidiary Guarantor any information concerning the Borrower
or any of its Subsidiaries, and the Subsidiary Guarantor has made arrangements
satisfactory to the Subsidiary Guarantor to obtain from the Borrower on a
continuing basis such information concerning the Borrower and its Subsidiaries
as the Subsidiary Guarantor may desire.

            (c)   The Subsidiary Guarantor agrees that any statement of account
with respect to the Borrower Obligations from any Credit Party to the Borrower
which binds the Borrower shall also be binding upon the Subsidiary Guarantor,
and that copies of said statements of account maintained in the regular course
of or such Credit Party's business may be used in evidence against the
Subsidiary Guarantor in order to establish its Guarantor Obligations.

            (d)   The Subsidiary Guarantor acknowledges that it has received a
copy of the Loan Documents and has approved of the same. In addition, the
Subsidiary Guarantor acknowledges having read each Loan Document and having had
the advice of counsel in connection with all matters concerning its execution
and delivery of this Guaranty.

            (e)   This Guaranty shall be binding upon the Subsidiary Guarantor
and its successors and inure to the benefit of, and be enforceable by the
Administrative Agent, Lenders and their respective successors, transferees and
assigns. The Subsidiary Guarantor may not assign any right, or delegate any
duty, it may have under this Guaranty.

            (f)   Subject to the limitations set forth in Section 2(b), the
Guarantor Obligations shall be joint and several.

            (g)   This Guaranty is the "Guaranty" referred to in the Credit
Agreement, and is subject to, and should be construed in accordance with, the
provisions thereof. Each of the parties hereto acknowledges and agrees that the
following are made applicable to this Guaranty and all such provisions are
incorporated by reference herein as if fully set forth herein, including
Sections 1 (Definitions), 2.13 (Taxes; Net Payments), 9.1 (Events of Default),
11.1 (Amendments and Waivers), 11.3 (No Waiver; Cumulative Remedies), 11.5
(Payment of Expenses and Taxes), 11.7 (Successors and Assigns), 11.9
(Counterparts), 11.12 (Indemnity), 11.13 (Governing Law), 11.14 (Headings
Descriptive), 11.15 (Severability), 11.16


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(Integration), 11.17 Consent to Jurisdiction), 11.18 (Service of Process), 11.19
(No Limitation on Service or Suit) and 11.20 (WAIVER OF TRIAL BY JURY).

            (h)   The Subsidiary Guarantor agrees that (i) the execution and
delivery of a Guaranty by any Required Additional Guarantor after the date
hereof shall not affect the obligations of the Subsidiary Guarantor hereunder,
and (ii) the Subsidiary Guarantor, each such Required Additional Guarantor and
each other guarantor under a Guaranty shall, subject to Section 2(b), be jointly
and severally liable for all of the Borrower Obligations.

            (i)   The undersigned Subsidiary Guarantor is a Required Additional
Guarantor and acknowledges and agrees that it is executing this Guaranty in
accordance with the requirements of the Credit Agreement in order to induce the
Credit Parties to make additional Loans and/or issue additional Letters of
Credit and as consideration for Loans and Letters of Credit previously made or
issued. The undersigned Subsidiary Guarantor agrees that, subject to Section
2(b), it is jointly and severally liable with all other Subsidiaries who have
previously executed and delivered a Guaranty pursuant to the Credit Agreement
for all of the Borrower Obligations.


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      IN EVIDENCE of the agreement by the parties hereto to the terms and
conditions herein contained, each such party has caused this Subsidiary
Guarantee to be duly executed on its behalf.

                                              ERT DEVELOPMENT CORPORATION


                                              By: /s/ Steven F. Siegel
                                                  ------------------------------
                                                  Steven F. Siegel
                                                  Sernior Vice President


                                              Address for Notices:

                                                  1120 Avenue of the Americas
                                                  New York, New York 10036
                                                  Attention:John B. Roche
                                                  Telephone:(212) 869-3000
                                                  Telecopy: (212) 302-4776


                                              THE BANK OF NEW YORK, as
                                              Administrative Agent

                                              By: /s/ Frederick Laudisi
                                                  ------------------------------
                                                  Frederick Laudisi
                                                  Vice President


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