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                                                                   EXHIBIT 10.49


                UNCONDITIONAL GUARANTY OF PAYMENT AND PERFORMANCE

        FOR AND IN CONSIDERATION OF the sum of Ten and No/100 Dollars ($10.00)
and other good and valuable consideration paid or delivered to the undersigned
NEW PLAN EXCEL REALTY TRUST, INC., a Maryland corporation, formerly known as
Excel Realty Trust, Inc. (hereinafter referred to as "Guarantor"), the receipt
and sufficiency whereof are hereby acknowledged by Guarantor, and for the
purpose of seeking to induce BANKBOSTON, N.A., a national banking association
(hereinafter referred to as "Lender", which term shall also include each other
Bank which may now or hereafter become party to the "Loan Agreement" (as
hereinafter defined) and shall also include BankBoston, N.A., as agent for all
of the Banks, and any other Bank that is hereafter acting as agent for all of
the Banks), to extend credit or otherwise provide financial accommodations to
BRIAR PRESTON RIDGE PARTNERS, L.P., a Texas limited partnership (hereinafter
referred to as "Borrower"), which extension of credit and provision of financial
accommodations will be to the direct interest, advantage and benefit of
Guarantor, Guarantor does hereby absolutely, unconditionally and irrevocably
guarantee to Lender:

        (a)     the full and prompt payment when due, whether by acceleration or
otherwise, either before or after maturity thereof, of that certain Amended and
Restated Note (hereinafter referred to as the "BKB Note"), dated December 30,
1998, made by Borrower to the order of BKB in the principal face amount of
SIXTY-EIGHT MILLION AND NO/100 DOLLARS ($68,000,000.00), together with interest
as provided in the BKB Note, together with any replacements, supplements,
renewals, modifications, consolidations, restatements and extensions thereof;
and

        (b)     the full and prompt payment when due, whether by acceleration or
otherwise, either before or after maturity thereof, of each other note as may be
issued under that certain First Amended and Restated Term Loan Agreement, dated
as of December 30, 1998 (hereinafter referred to as the "Loan Agreement") among
Borrower, BKB, for itself and as Agent, and the other Banks that may become a
party thereto, together with interest as provided in each such note, together
with any replacements, supplements, renewals, modifications, consolidations,
restatements and extensions thereof (the BKB Note and each of the notes
described in this subparagraph (b) is hereinafter referred to collectively as
the "Note"); and

        (c)     the full and prompt payment and performance of all obligations
of Borrower to Lender under the terms of the Loan Agreement, together with any
replacements, supplements, renewals, modifications, consolidations, restatements
and extensions thereof; and

        (d)     the full and prompt payment and performance of any and all
obligations of Borrower under the terms of the "Deed of Trust" (as defined in
the Loan Agreement) from Borrower relating to certain real property more
particularly described therein (such real property is hereinafter referred to as
the "Land"), together with any replacements, supplements, renewals,
modifications, consolidations, restatements and extensions thereof, including,
without limitation, 


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the obligations of Borrower concerning hazardous materials contained in
paragraph 7 of the Deed of Trust; and

        (e)     the full and prompt payment and performance of any and all other
obligations of Borrower to Lender under any other agreements, documents or
instruments now or hereafter evidencing, securing or otherwise relating to the
indebtedness evidenced by the Note or the Loan Agreement (the Note, the Loan
Agreement, the Deed of Trust and said other agreements, documents and
instruments are hereinafter collectively referred to as the "Loan Documents" and
individually referred to as a "Loan Document").

        All terms used herein and not otherwise defined herein shall have the
meanings set forth in the Loan Agreement. This Guaranty is executed and
delivered by Guarantor in amendment and restatement of that certain
Unconditional Guaranty of Payment and Performance dated as of December 30, 1997,
made by Excel Realty Trust, Inc. in favor of Lender, and in amendment and
restatement of that certain Unconditional Guaranty of Payment and Performance
dated as of December 30, 1998, made by New Plan Excel Realty Trust, Inc. in
favor of Lender.

        1.      Agreement to Pay and Perform; Costs of Collection. Guarantor
does hereby agree that if the Note is not paid by Borrower in accordance with
its terms, or if any and all sums which are now or may hereafter become due from
Borrower to Lender under the Loan Documents are not paid by Borrower in
accordance with their terms, or if any and all other obligations of Borrower to
Lender under the Note and the Loan Documents are not performed by Borrower in
accordance with their terms, Guarantor will immediately make such payments and
perform such obligations. Guarantor further agrees to pay Lender on demand all
reasonable costs and expenses (including court costs and reasonable attorneys'
fees and disbursements) paid or incurred by Lender in endeavoring to collect the
indebtedness guaranteed hereby, to enforce any of the other obligations of
Borrower guaranteed hereby, or any portion thereof, or to enforce this Guaranty,
and until paid to Lender, such sums shall bear interest at the default rate of
interest provided in the Loan Agreement unless collection from Guarantor of
interest at such rate would be contrary to applicable law, in which event such
sums shall bear interest at the highest rate which may be collected from
Guarantor under applicable law.

        2.      Reinstatement of Refunded Payments. If, for any reason, any
payment to Lender of any of the obligations guaranteed hereunder is required to
be refunded by Lender to Borrower, or paid or turned over to any other person,
including, without limitation, by reason of the operation of bankruptcy,
reorganization, receivership or insolvency laws or similar laws of general
application relating to creditors' rights and remedies now or hereafter enacted,
Guarantor agrees to pay the amount so required to be refunded, paid or turned
over (the "Turnover Payment"), and the obligations of Guarantor shall not be
treated as having been discharged by the original payment to Lender giving rise
to the Turnover Payment, and this Guaranty shall be treated as having remained
in full force and effect for any such Turnover Payment so made by Lender, as
well as for any amounts not theretofore paid to Lender on account of such
obligations.


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        3.      Rights of Lender to Deal with Collateral, Borrower and Other
Persons. Guarantor hereby consents and agrees that Lender may at any time, and
from time to time, without thereby releasing Guarantor from any liability
hereunder and without notice to or further consent from Guarantor, either with
or without consideration: release or surrender any lien or other security of any
kind or nature whatsoever held by it or by any person, firm or corporation on
its behalf or for its account, securing any indebtedness or liability hereby
guaranteed; substitute for any collateral so held by it, other collateral of
like kind, or of any kind; modify the terms of the Note or the Loan Documents;
extend or renew the Note for any period; grant releases, compromises and
indulgences with respect to the Note or the Loan Documents and to any persons or
entities now or hereafter liable thereunder or hereunder; release any other
Guarantor, surety, endorser or accommodation party of the Note, the Security
Deed or any other Loan Documents; or take or fail to take any action of any type
whatsoever. No such action which Lender shall take or fail to take in connection
with the Note or the Loan Documents, or any of them, or any security for the
payment of the indebtedness of Borrower to Lender or for the performance of any
obligations or undertakings of Borrower, nor any course of dealing with Borrower
or any other person, shall release Guarantor's obligations hereunder, affect
this Guaranty in any way or afford Guarantor any recourse against Lender. The
provisions of this Guaranty shall extend and be applicable to all replacements,
supplements, renewals, amendments, extensions, consolidations, restatements and
modifications of the Note and the Loan Documents, and any and all references
herein to the Note and the Loan Documents shall be deemed to include any such
replacements, supplements, renewals, extensions, amendments, consolidations,
restatements or modifications thereof.

        4.      No Contest with Lender; Subordination. So long as any obligation
hereby guaranteed remains unpaid or undischarged, Guarantor will not, by paying
any sum recoverable hereunder (whether or not demanded by Lender) or by any
means or on any other ground, claim any set-off or counterclaim against Borrower
in respect of any liability of Guarantor to Borrower or, in proceedings under
federal bankruptcy law or insolvency proceedings of any nature, prove in
competition with Lender in respect of any payment hereunder or be entitled to
have the benefit of any counterclaim or proof of claim or dividend or payment by
or on behalf of Borrower or the benefit of any other security for any obligation
hereby guaranteed which, now or hereafter, Lender may hold or in which it may
have any share. So long as any obligation hereby guaranteed remains unpaid or
undischarged, Guarantor hereby expressly waives any right of contribution from
or indemnity against Borrower, whether at law or in equity, arising from any
payments made by Guarantor pursuant to the terms of this Guaranty, and Guarantor
acknowledges that Guarantor has no right whatsoever to proceed against Borrower
for reimbursement of any such payments. In connection with the foregoing,
Guarantor expressly waives any and all rights of subrogation to Lender against
Borrower, and Guarantor hereby waives any rights to enforce any remedy which
Lender may have against Borrower and any rights to participate in any collateral
for Borrower's obligations under the Loan Documents. Guarantor hereby
subordinates any and all indebtedness of Borrower now or hereafter owed to
Guarantor to all indebtedness of Borrower to Lender, and agrees with Lender that
(a) Guarantor shall not demand or accept any payment from Borrower on account of
such indebtedness, unless such payment is approved by Lender in the exercise of
its sole discretion, (b) Guarantor shall not claim any offset or other reduction
of 


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Guarantor's obligations hereunder because of any such indebtedness, and (c)
Guarantor shall not take any action to obtain any interest in any of the
security described in and encumbered by the Loan Documents because of any such
indebtedness; provided, however, that, if Lender so requests, such indebtedness
shall be collected, enforced and received by Guarantor as trustee for Lender and
be paid over to Lender on account of the indebtedness of Borrower to Lender, but
without reducing or affecting in any manner the liability of Guarantor under the
other provisions of this Guaranty except to the extent the principal amount of
such outstanding indebtedness shall have been reduced by such payment.

        5.      Waiver of Defenses. Guarantor hereby agrees that its obligations
hereunder shall not be affected or impaired by, and hereby waives and agrees not
to assert or take advantage of any defense based on:

                (a)     any statute of limitations in any action hereunder or
for the collection of the Note or for the payment or performance of any
obligation hereby guaranteed;

                (b)     the incapacity, lack of authority, death or disability
of Borrower or any other person or entity, or the failure of Lender to file or
enforce a claim against the estate (either in administration, bankruptcy or in
any other proceeding) of Borrower or Guarantor or any other person or entity;

                (c)     the dissolution or termination of existence of Borrower
or Guarantor;

                (d)     the voluntary or involuntary liquidation, sale or other
disposition of all or substantially all of the assets of Borrower;

                (e)     the voluntary or involuntary receivership, insolvency,
bankruptcy, assignment for the benefit of creditors, reorganization, assignment,
composition, or readjustment of, or any similar proceeding affecting, Borrower
or Guarantor, or any of Borrower's or Guarantor's properties or assets;

                (f)     the damage, destruction, condemnation, foreclosure or
surrender of all or any part of the Land or any improvements now or hereafter
located on the Land (the "Improvements");

                (g)     any change in the plans and specifications relating to
the construction of the Improvements;

                (h)     any modification of the terms of any contract relating
to the construction of the Improvements or the furnishing of any labor,
equipment, supplies or materials therefor;


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                (i)     the failure of Lender to give notice of the existence,
creation or incurring of any new or additional indebtedness or obligation or of
any action or nonaction on the part of any other person whomsoever in connection
with any obligation hereby guaranteed;

                (j)     any failure or delay of Lender to commence an action
against Borrower or any other Person, to assert or enforce any remedies against
Borrower under the Note or the Loan Documents, or to realize upon any security;

                (k)     any failure of any duty on the part of Lender to
disclose to Guarantor any facts it may now or hereafter know regarding Borrower,
the Land or any of the Improvements, whether such facts materially increase the
risk to Guarantor or not;

                (l)     failure to accept or give notice of acceptance of this
Guaranty by Lender;

                (m)     failure to make or give notice of presentment and demand
for payment of any of the indebtedness or performance of any of the obligations
hereby guaranteed;

                (n)     failure to make or give protest and notice of dishonor
or of default to Guarantor or to any other party with respect to the
indebtedness or performance of obligations hereby guaranteed;

                (o)     any and all other notices whatsoever to which Guarantor
might otherwise be entitled;

                (p)     any lack of diligence by Lender in collection,
protection or realization upon any collateral securing the payment of the
indebtedness or performance of obligations hereby guaranteed;

                (q)     the invalidity or unenforceability of the Note or any of
the Loan Documents;

                (r)     the compromise, settlement, release or termination of
any or all of the obligations of Borrower under the Note or the Loan Documents;

                (s)     any transfer by Borrower or any other Person of all or
any part of the security encumbered by the Loan Documents;

                (t)     any exculpation or limitation of liability contained in
the Note or in the Loan Documents;

                (u)     the failure of Lender to perfect any security or to
extend or renew the perfection of any security;


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                (v)     the failure of Guarantor to receive payment of any fees
or other sums at any time payable by Borrower or any other person in connection
with the execution and delivery by Guarantor of the Guaranty or in connection
with the ownership, development or operation of the Land or any Improvements; or

                (w)     to the fullest extent permitted by law, any other legal,
equitable or surety defenses whatsoever to which Guarantor might otherwise be
entitled, it being the intention that the obligations of Guarantor hereunder are
absolute, unconditional and irrevocable.

        6.      Guaranty of Payment and Performance and Not of Collection. This
is a Guaranty of payment and performance and not of collection. The liability of
Guarantor under this Guaranty shall be primary, direct and immediate and not
conditional or contingent upon the pursuit of any remedies against Borrower or
any other person, nor against securities or liens available to Lender, its
successors, successors in title, endorsees or assigns. Guarantor hereby waives
any right to require that an action be brought against Borrower or any other
person or to require that resort be had to any security or to any balance of any
deposit account or credit on the books of Lender in favor of Borrower or any
other person.

        7.      Rights and Remedies of Lender. In the event of a default under
the Note or the Loan Documents, or any of them, Lender shall have the right to
enforce its rights, powers and remedies thereunder or hereunder or under any
other agreement, document or instrument now or hereafter evidencing, securing or
otherwise relating to the indebtedness evidenced by the Note or secured by the
Loan Documents, in any order, and all rights, powers and remedies available to
Lender in such event shall be nonexclusive and cumulative of all other rights,
powers and remedies provided thereunder or hereunder or by law or in equity.
Accordingly, Guarantor hereby authorizes and empowers Lender upon the occurrence
of any event of default under the Note or the Loan Documents, at its sole
discretion, and without notice to Guarantor, to exercise any right or remedy
which Lender may have, including, but not limited to, judicial foreclosure,
exercise of rights of power of sale, acceptance of a deed or assignment in lieu
of foreclosure, appointment of a receiver to collect rents and profits, exercise
of remedies against personal property, or enforcement of any assignment of
leases, as to any security, whether real, personal or intangible. At any public
or private sale of any security or collateral for any indebtedness or any part
thereof guaranteed hereby, whether by foreclosure or otherwise, Lender may, in
its discretion, purchase all or any part of such security or collateral so sold
or offered for sale for its own account and may apply against the amount bid
therefor all or any part of the balance due it pursuant to the terms of the Note
or Security Deed or any other Loan Document without prejudice to Lender's
remedies hereunder against Guarantor for deficiencies. If the indebtedness
guaranteed hereby is partially paid by reason of the election of Lender to
pursue any of the remedies available to Lender, or if such indebtedness is
otherwise partially paid, this Guaranty shall nevertheless remain in full force
and effect, and Guarantor shall remain liable for the entire balance of the
indebtedness guaranteed hereby even though any rights which Guarantor may have
against Borrower may be destroyed or diminished by the exercise of any such
remedy.


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        8.      Application of Payments. Guarantor hereby authorizes Lender,
without notice to Guarantor, to apply all payments and credits received from
Borrower or from Guarantor or realized from any security in such manner and in
such priority as Lender in its sole judgment shall see fit to the indebtedness,
obligation and undertakings which are the subject of this Guaranty.

        9.      Business Failure, Bankruptcy or Insolvency. In the event of the
business failure of Guarantor or if there shall be pending any bankruptcy or
insolvency case or proceeding with respect to Guarantor under federal bankruptcy
law or any other applicable law or in connection with the insolvency of
Guarantor, or if a liquidator, receiver, or trustee shall have been appointed
for Guarantor or Guarantor's properties or assets, Lender may file such proofs
of claim and other papers or documents as may be necessary or advisable in order
to have the claims of Lender allowed in any proceedings relative to Guarantor,
or any of Guarantor's properties or assets, and, irrespective of whether the
indebtedness or other obligations of Borrower guaranteed hereby shall then be
due and payable, by declaration or otherwise, Lender shall be entitled and
empowered to file and prove a claim for the whole amount of any sums or sums
owing with respect to the indebtedness or other obligations of Borrower
guaranteed hereby, and to collect and receive any moneys or other property
payable or deliverable on any such claim. Guarantor covenants and agrees that
upon the commencement of a voluntary or involuntary bankruptcy proceeding by or
against Borrower, Guarantor shall not seek a supplemental stay or otherwise
pursuant to 11 U.S.C. Section 105 or any other provision of the Bankruptcy
Reform Act of 1978, as amended, or any other debtor relief law (whether
statutory, common law, case law, or otherwise) of any jurisdiction whatsoever,
now or hereafter in effect, which may be or become applicable, to stay,
interdict, condition, reduce or inhibit the ability of Lender to enforce any
rights of Lender against Guarantor by virtue of this Guaranty or otherwise.

        10.     Financial Statements and Other Information. Guarantor hereby
represents and warrants to Lender that all financial statements of Guarantor and
its subsidiaries heretofore delivered by Guarantor to Lender are true and
correct in all material respects, have been prepared in accordance with
generally accepted accounting principles consistently applied, and fairly
present the financial condition of Guarantor as at the close of business on the
date thereof and the results of operations for the period then ended; that no
material adverse change has occurred in the assets, liabilities, financial
condition or business of Guarantor as shown or reflected therein since the date
thereof; and that Guarantor and its subsidiaries have no liabilities or known
contingent liabilities which are not reflected in such financial statements or
referred to in the notes thereto other than Guarantor's obligations under this
Guaranty. Guarantor hereby agrees that until all indebtedness guaranteed hereby
has been completely repaid and all obligations and undertakings of Borrower
under, by reason of, or pursuant to the Note and the Loan Documents have been
completely performed, Guarantor will deliver to Lender:

                (a)     as soon as practicable and in any event within 90 days
after the end of each fiscal year of Guarantor, the consolidated balance sheet
of Guarantor and its subsidiaries as of the end of such year (accompanied by
supplementary schedules indicating the total debt on 


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any assets shown on a net investment basis), and the related statement of
income, statement of changes in capital and statement of cash flows for such
year, each setting forth in comparative form the figures for the previous fiscal
year and all such statements to be in reasonable detail, prepared in accordance
with generally accepted accounting principles, and accompanied by an auditor's
report prepared without qualification by an accounting firm acceptable to
Lender, the Form 10-K filed with the federal Securities and Exchange Commission
("SEC") (unless the SEC has approved an extension, in which event the Guarantor
will deliver to each Lender a copy of the Form 10-K simultaneously with delivery
to the SEC), and any other information the Lender reasonably may need to
complete a financial analysis of Guarantor;

                (b)     as soon as practicable and in any event within 45 days
after the end of each of the fiscal quarters of Guarantor (including the fourth
fiscal quarter in each year), copies of Form 10-Q filed with the SEC (unless the
SEC has approved an extension in which event the Guarantor will deliver such
copies of the Form 10-Q to each Lender simultaneously with delivery to the SEC);
the unaudited consolidated balance sheet of Guarantor and its subsidiaries as of
the end of such quarter, and the related statement of income, statement of
changes in capital and statement of cash flows for the portion of Guarantor's
fiscal year then elapsed, and the compliance certificate required to be
delivered to the agent and the lenders pursuant to the Credit Agreement, all in
reasonable detail and prepared in accordance with generally accepted accounting
principles, together with a certification by the principal financial or
accounting officer of Guarantor that the information contained in such financial
statements fairly presents the financial position of Guarantor and its
subsidiaries on the date thereof (subject to year end adjustment);

                (c)     contemporaneously with the delivery of the financial
statements referred to in clause (a) above, a statement of all contingent
liabilities of Guarantor and its subsidiaries which are not reflected in such
financial statements or referred to in the notes thereto (including, without
limitation, all guarantees, endorsements and other contingent obligations in
respect of indebtedness of others, and obligations to reimburse the issuer in
respect of any letters of credit), all in reasonable detail and certified by the
principal financial or accounting officer of Guarantor;

                (d)     contemporaneously with the filing or mailing thereof,
copies of all material of a financial nature filed with the SEC or sent to the
stockholders of Guarantor;

                (e)     promptly after they are filed with the Internal Revenue
Service, copies of all annual federal income tax returns and amendments thereto
of Guarantor;

                (f)     promptly upon becoming aware thereof, written notice
from Guarantor of any event or condition which might have a material adverse
effect on the business, operations, assets, condition (financial or otherwise)
of Guarantor or any of its subsidiaries or the ability of Guarantor to perform
under this Guaranty (including but not limited to, litigation commenced against
Guarantor or any of its subsidiaries, judgments rendered against Guarantor or
any of its subsidiaries, liens filed against any property of Guarantor or any of
its subsidiaries, defaults 


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claimed under indebtedness for borrowed money for which Guarantor or any of its
subsidiaries is primarily or secondarily liable, or bankruptcy, insolvency or
trustee or receivership proceedings commenced against Guarantor or any of its
subsidiaries), such notice to specify the nature and the period of existence of
such event or condition, the anticipated effect thereof, and what action
Guarantor is taking or proposes to take with respect thereto; and

                (g)     with reasonable promptness, such other information
respecting the business, operations, assets, liabilities and financial condition
of Guarantor and its subsidiaries as Lender may from time to time reasonably
request.

Upon two (2) Business Days' prior notice, Guarantor will permit any officer
designated by Lender, at Guarantor's expense, to visit and inspect any of the
properties of Guarantor or any of its subsidiaries, to examine the records and
books of account of Guarantor and its subsidiaries (and to make copies thereof
and extracts therefrom) and to discuss the affairs, finances and accounts of
Guarantor and its subsidiaries with, and to be advised as to the same by, its
officers, all at such reasonable times and intervals Lender may reasonably
request.

        11.     Covenants of Guarantor. Guarantor hereby covenants and agrees
with Lender that until all indebtedness guaranteed hereby has been completely
repaid and all obligations and undertakings of Borrower under, by reason of, or
pursuant to the Note and the Loan Documents have been completely performed:

                (a)     Guarantor will, and will cause each of its subsidiaries
to, do or cause to be done all things necessary to preserve and keep in full
force and effect its corporate or legal existence, rights and franchises, to
effect and maintain its foreign qualifications, licensing, domestication or
authorization, except where a failure to be so qualified, licensed, domesticated
or authorized in such foreign jurisdictions would not have a materially adverse
effect on its business, assets or financial condition, and to comply with all
applicable laws and regulations (including, without limitation, environmental
laws);

                (b)     Guarantor will, and will cause each of its subsidiaries
to, continue to engage primarily in the business now conducted by it and them;

                (c)     Guarantor will, and will cause each of its subsidiaries
to, duly pay and discharge, before the same shall become in arrears, all taxes,
assessments and other governmental charges imposed upon it and its properties,
sales or activities, or upon the income or profits therefrom, as well as claims
for labor, material, or supplies which if unpaid might become a lien or charge
on any of its property; provided that any such tax, assessment, charge or claim
need not be paid if the validity or amount thereof shall currently be contested
in good faith by appropriate proceedings and if Guarantor or such subsidiary
shall have set aside on its books adequate reserves with respect thereto; and
provided further that Guarantor or such subsidiary shall pay all such taxes,
assessments, charges and claims forthwith upon the commencement of proceedings
to foreclose any lien that may have attached as security therefor;


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                (d)     Guarantor will, and will cause each of its subsidiaries
to, maintain and keep the properties used or deemed by it to be useful in its
business in first-class repair, working order and condition, and make or cause
to be made all necessary and proper repairs thereto and replacements thereof;

                (e)     Guarantor will, and will cause each of its subsidiaries
to, maintain with financially sound and reputable insurers, insurance with
respect to its properties and business against such casualties and contingencies
and in such types and amounts as shall be in accordance with sound business
practices for companies in similar business similarly situated;

                (f)     Guarantor will keep, and will cause each of its
subsidiaries to keep, complete, proper and accurate records and books of account
in which full, true and correct entries will be made in accordance with
generally accepted accounting principles consistent with the preparation of the
financial statements heretofore delivered to Lender and will maintain adequate
accounts and reserves for all taxes (including income taxes), all depreciation,
depletion, and amortization of its properties and the properties of its
subsidiaries, all other contingencies, and all other proper reserves;

                (g)     Guarantor will not, and will not permit any of its
subsidiaries to, become a party to any merger, consolidation or other business
combination, or agree to effect any asset acquisition other than the acquisition
of assets in the ordinary course of business consistent with past practices,
stock acquisition or other acquisition, except (A) the merger or consolidation
of one or more of the subsidiaries of Guarantor with and into Guarantor, or (B)
the merger or consolidation of two or more subsidiaries of Guarantor, or (C) the
merger of Guarantor with another entity provided that Guarantor is the surviving
entity;

                (h)     Guarantor will not, and will not permit any of its
subsidiaries to, become a party to or agree to or affect any disposition of
assets, other than the disposition of assets in the ordinary course of business
consistent with past practice;

                (i)     Guarantor will not make or permit to be made, by
voluntary or involuntary means, any transfer or encumbrance of its interest in
ERT Development Corporation, or any dilution of its interest in ERT Development
Corporation; provided, however, Guarantor may assign up to fifty percent (50%)
of the issued and outstanding shares of preferred stock in ERT Development
Corporation owned by Guarantor to the officers of Guarantor;

               (j)     Guarantor shall at all times comply with all requirements
of applicable laws and regulations necessary to maintain its status as a real
estate investment trust as defined in Section 856(a) of the Code and in
compliance with the terms and conditions of this Guaranty and the other Loan
Documents;


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                (k)     Guarantor shall at all times observe, perform and comply
with each and every term, covenant or agreement set forth in the Credit
Agreement within any applicable period of grace or notice and cure, and, in the
event that the Credit Agreement shall be terminated or no longer in full force
and effect, Guarantor shall continue to observe, perform and comply with the
terms, covenants and agreements therein as the same existed immediately prior to
such termination as if the same continued in full force and effect; and

                (l)     Guarantor will cooperate with Lender and execute such
further instruments and documents as Lender shall reasonably request to carry
out to their satisfaction the transactions contemplated by this Guaranty and the
other Loan Documents.

        12.     Security and Rights of Set-off. Guarantor hereby grants to
Lender, as security for the full and prompt payment and performance of
Guarantor's obligations hereunder, a continuing lien on and security interest in
any and all securities or other property belonging to Guarantor now or hereafter
held by Lender and in any and all deposits (general or specific, time or demand,
provisional or final, regardless of currency, maturity, or the branch of Lender
where the deposits are held) now or hereafter held by Lender and other sums
credited by or due from Lender to Guarantor or subject to withdrawal by
Guarantor; and regardless of the adequacy of any collateral or other means of
obtaining repayment of such obligations, during the continuance of any Event of
Default under the Note or the Loan Documents, Lender may at any time and without
notice to Guarantor set-off and apply the whole or any portion or portions of
any or all such deposits and other sums against amounts payable under this
Guaranty, whether or not any other person or persons could also withdraw money
therefrom. Any security now or hereafter held by or for Guarantor and provided
by Borrower, or by anyone on Borrower's behalf, in respect of liabilities of
Guarantor hereunder shall be held in trust for Lender as security for the
liabilities of Guarantor hereunder.

        13.     Changes in Writing; No Revocation. This Guaranty may not be
changed orally, and no obligation of Guarantor can be released or waived by
Lender except by a writing signed by a duly authorized officer of Lender. This
Guaranty shall be irrevocable by Guarantor until all indebtedness guaranteed
hereby has been completely repaid and all obligations and undertakings of
Borrower under, by reason of, or pursuant to the Note and the Loan Documents
have been completely performed.

        14.     Notices. All notices, demands or requests provided for or
permitted to be given pursuant to this Guaranty (hereinafter in this paragraph
referred to as "Notice") must be in writing and shall be deemed to have been
properly given or served by personal delivery or by sending same by overnight
courier or by depositing the same in the United States mail, postpaid and
registered or certified, return receipt requested, at the addresses set forth
below. Each Notice shall be effective upon being delivered personally or upon
being sent by overnight courier or upon being deposited in the United States
Mail as aforesaid. The time period in which a response to any such Notice must
be given or any action taken with respect thereto, however, shall commence to
run from the date of receipt if personally delivered or sent by overnight


                                      -11-
<PAGE>   12
courier or, if so deposited in the United States Mail, the earlier of three (3)
Business Days following such deposit and the date of receipt as disclosed on the
return receipt. Rejection or other refusal to accept or the inability to deliver
because of changed address of which no Notice was given shall be deemed to be
receipt of the Notice sent. By giving at least thirty (30) days prior Notice
thereof, Guarantor or Lender shall have the right from time to time and at any
time during the term of this Guaranty to change their respective addresses and
each shall have the right to specify as its address any other address within the
United States of America. For the purposes of this Guaranty:

        The address of Lender is:

                BankBoston, N.A.
                100 Federal Street
                Boston, Massachusetts 02110
                Attn:  Real Estate Division

        with a copy to:

                BankBoston, N.A.
                115 Perimeter Center Place, N.E.
                Suite 500
                Atlanta, Georgia 30346
                Attn: Jeffrey L. Warwick

and a copy to each other Bank which may now or hereafter become a party to the
Loan Agreement at such address as may be designated by such Bank.

        The address of Guarantor is:

                New Plan Excel Realty Trust, Inc.
                16955 Via Del Campo
                Suite 110
                San Diego, California  92127
                Attn: Richard B. Muir

        15.     GOVERNING LAW. GUARANTOR AND LENDER ACKNOWLEDGE AND AGREE THAT
THIS GUARANTY AND THE OBLIGATIONS OF GUARANTOR HEREUNDER SHALL BE GOVERNED BY
AND INTERPRETED AND DETERMINED IN ACCORDANCE WITH THE LAWS OF THE OF
MASSACHUSETTS (EXCLUDING THE LAWS APPLICABLE TO CONFLICTS OR CHOICE OF LAW).


                                      -12-
<PAGE>   13
        If, notwithstanding the provisions of Section 15 above, this Guaranty is
deemed to be governed by California law, then the following shall apply but
shall not in any way limit the generality of any other provisions contained in
this Guaranty.

        Guarantor hereby waives (a) any defense of Guarantor based upon Lender's
election of any remedy against Guarantor or Borrower or both; (b) any defense
based upon Lender's failure to disclose to Guarantor any information concerning
Borrower's financial condition or any other circumstances bearing on Borrower's
ability to pay all sums payable under the Loan Documents; (c) any defense based
upon any statute or rule of law which provides that the obligation of a surety
must be neither larger in amount nor in any other respects more burdensome than
that of a principal; (d) any defense based upon Lender's election, in any
proceeding instituted under the Federal Bankruptcy Code, of the application of
Section 1111(b)(2) of the Federal Bankruptcy Code or any successor statute; (e)
any right of subrogation, any right to enforce any remedy which Lender may have
against Borrower and any right to participate in, or benefit from, any security
for any of the Loan Documents now or hereafter held by Lender; and (f) benefit
of any statute of limitations affecting the liability of the Guarantor hereunder
or the enforcement hereof. Without limiting the generality of the foregoing or
any other provision hereof, Guarantor expressly waives any and all benefits
which might otherwise be available to Guarantor under Sections 2787 to 2855,
inclusive, of the California Civil Code, including without limitation, Sections
2809, 2810, 2819, 2839, 2845, 2849 and 2850, and all benefits which might
otherwise be available to Guarantor under Sections 2899 and 3433 of the
California Civil Code and the California Code of Civil Procedure Sections 580a,
580b, 580d and 726, or any of such sections. Furthermore, without limitation of
any waiver otherwise set forth herein, Guarantor waives all rights and defenses
arising out of an election of remedies by the Lender even though that election
of remedies, such as a nonjudicial foreclosure with respect to the security for
a guaranteed obligation, has destroyed Guarantor's rights of subrogation and
reimbursement against the principal by operation of Section 580d of the
California Code of Civil Procedure or otherwise.

        In addition, Guarantor waives all rights and defenses that Guarantor may
have because the Borrower's debt is secured by real property. This means, among
other things:

         (A) Lender may collect from Guarantor without first foreclosing on any
real or personal property collateral pledged by Borrower; and

         (B) If Lender forecloses on any real property collateral pledged by
Borrower:

                (i)     The amount of the debt may be reduced only by the price
for which that collateral is sold at the foreclosure sale, even if the
collateral is worth more than the sale price;

                (ii)    Lender may collect from Guarantor even if Lender, by
foreclosing on the real property collateral, has destroyed any right Guarantor
may have to collect from Borrower.


                                      -13-
<PAGE>   14
        This is an unconditional and irrevocable waiver of any rights and
defenses Guarantor may have because Borrower's debt is secured by real property.
These rights and defenses include, but are not limited to, any rights or
defenses based upon Section 580a, 580b, 580d or 726 of the California Code of
Civil Procedure.

        16.     CONSENT TO JURISDICTION; WAIVERS. GUARANTOR HEREBY IRREVOCABLY
AND UNCONDITIONALLY (A) SUBMITS TO PERSONAL JURISDICTION IN THE STATE OF
MASSACHUSETTS OVER ANY SUIT, ACTION OR PROCEEDING ARISING OUT OF OR RELATING TO
THIS GUARANTY, AND (B) WAIVES ANY AND ALL PERSONAL RIGHTS UNDER THE LAWS OF ANY
STATE (I) TO THE RIGHT, IF ANY, TO TRIAL BY JURY, (II) TO OBJECT TO JURISDICTION
WITHIN THE STATE OF MASSACHUSETTS OR VENUE IN ANY PARTICULAR FORUM WITHIN THE
STATE OF MASSACHUSETTS, AND (III) TO THE RIGHT, IF ANY, TO CLAIM OR RECOVER ANY
SPECIAL, EXEMPLARY, PUNITIVE OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES OTHER THAN
ACTUAL DAMAGES. EACH LENDER IRREVOCABLY AND UNCONDITIONALLY WAIVES ANY AND ALL
RIGHTS UNDER THE LAWS OF ANY STATE TO THE RIGHT, IF ANY, TO TRIAL BY JURY.
GUARANTOR AGREES THAT, IN ADDITION TO ANY METHODS OF SERVICE OF PROCESS PROVIDED
FOR UNDER APPLICABLE LAW, ALL SERVICE OF PROCESS IN ANY SUCH SUIT, ACTION OR
PROCEEDING MAY BE MADE BY CERTIFIED OR REGISTERED MAIL, RETURN RECEIPT
REQUESTED, DIRECTED TO GUARANTOR AT THE ADDRESS SET FORTH IN PARAGRAPH 14 ABOVE,
AND SERVICE SO MADE SHALL BE COMPLETE FIVE (5) DAYS AFTER THE SAME SHALL BE SO
MAILED. NOTHING CONTAINED HEREIN, HOWEVER, SHALL PREVENT LENDER FROM BRINGING
ANY SUIT, ACTION OR PROCEEDING OR EXERCISING ANY RIGHTS AGAINST ANY SECURITY AND
AGAINST GUARANTOR PERSONALLY, AND AGAINST ANY PROPERTY OF GUARANTOR, WITHIN ANY
OTHER STATE. INITIATING SUCH SUIT, ACTION OR PROCEEDING OR TAKING SUCH ACTION IN
ANY STATE SHALL IN NO EVENT CONSTITUTE A WAIVER OF THE AGREEMENT CONTAINED
HEREIN THAT THE LAWS OF THE COMMONWEALTH OF MASSACHUSETTS SHALL GOVERN THE
RIGHTS AND OBLIGATIONS OF GUARANTOR AND LENDER HEREUNDER OR OF THE SUBMISSION
HEREIN MADE BY GUARANTOR TO PERSONAL JURISDICTION WITHIN THE STATE OF
MASSACHUSETTS. GUARANTOR HEREBY WAIVES ANY OBJECTION THAT IT MAY NOW OR
HEREAFTER HAVE TO THE VENUE OF ANY SUCH SUIT OR ANY SUCH COURT OR THAT SUCH SUIT
IS BROUGHT IN AN INCONVENIENT COURT. GUARANTOR CERTIFIES THAT NO REPRESENTATIVE,
AGENT OR ATTORNEY OF ANY LENDER HAS REPRESENTED, EXPRESSLY OR OTHERWISE, THAT
SUCH LENDER WOULD NOT, IN THE EVENT OF LITIGATION, SEEK TO ENFORCE THEIR
FOREGOING WAIVERS AND ACKNOWLEDGES THAT LENDER HAS BEEN INDUCED TO ENTER INTO
THIS GUARANTY AND THE OTHER LOAN DOCUMENTS TO WHICH THEY ARE PARTIES BY, AMONG
OTHER THINGS, THE WAIVERS AND CERTIFICATIONS CONTAINED IN THIS PARAGRAPH 16. 


                                      -14-
<PAGE>   15
        17.     Successors and Assigns. The provisions of this Guaranty shall be
binding upon Guarantor and its heirs, successors, successors in title, legal
representatives, and assigns, and shall inure to the benefit of Lender, its
successors, successors in title, legal representatives and assigns.

        18.     Assignment by Lender. This Guaranty is assignable by Lender in
whole or in part in conjunction with any assignment of the Note or portions
thereof, and any assignment hereof or any transfer or assignment of the Note or
portions thereof by Lender shall operate to vest in any such assignee the rights
and powers, in whole or in part, as appropriate, herein conferred upon and
granted to Lender.

        19.     Severability. If any term or provision of this Guaranty shall be
determined to be illegal or unenforceable, all other terms and provisions hereof
shall nevertheless remain effective and shall be enforced to the fullest extent
permitted by law.

        20.     Disclosure. Guarantor agrees that in addition to disclosures
made in accordance with standard banking practices, any Lender may disclose
information obtained by such Lender pursuant to this Guaranty to assignees or
participants and potential assignees or participants hereunder.

        21.     NO UNWRITTEN AGREEMENTS. THIS GUARANTY REPRESENTS THE FINAL
AGREEMENT BETWEEN THE PARTIES AND MAY NOT BE CONTRADICTED BY EVIDENCE OF PRIOR,
CONTEMPORANEOUS OR SUBSEQUENT ORAL AGREEMENTS OF THE PARTIES. THERE ARE NO
UNWRITTEN ORAL AGREEMENTS BETWEEN THE PARTIES.

        22.     Time of the Essence. Time is of the essence with respect to each
and every covenant, agreement and obligation of Guarantor under this Guaranty.

        23.     Incorporation of Covenants. In the event that the loans
contemplated by the Credit Agreement shall be paid in full and the Credit
Agreement terminated, then Guarantor shall at all times thereafter observe,
perform and comply with each and every covenant set forth in the Credit
Agreement as of the date hereof (or as the same may be amended), as if such
covenants and any defined terms referred to therein were fully set forth in this
Guaranty and a part hereof, subject, however, to any applicable period of grace
or notice and cure with respect to a failure to comply with such covenants as
set forth in the Credit Agreement, if any.

        IN WITNESS WHEREOF, Guarantor has executed this Guaranty as of the 13th
day of January, 1999.

                                       NEW PLAN EXCEL REALTY
                                       TRUST, INC., a Maryland
                                       corporation, formerly known
                                       as Excel Realty Trust, Inc.


                                      -15-
<PAGE>   16
                                       By:  /s/ S. Eric Ottesen
                                            ------------------------------------
                                            Name:  S. Eric Ottesen
                                            Title:  Senior Vice President

                                                    [CORPORATE SEAL]


                                      -16-