August 9, 1999

Heller Financial, Inc.
500 West Monroe Street, 30th Floor
Chicago, IL 60661
Attn:  Heller Express Servicing Dept.
       Re: Loan No. 99-086

          Re:  $32,000,000.00  Loan  ("Loan")  from Heller  Financial,  Inc.,  a
               Delaware  corporation  ("Lender")  to 475  Fifth  Avenue  Limited
               Partnership, a Delaware limited partnership ("Borrower")

Ladies & Gentlemen:

       Reference is hereby made to the  above-referenced  Loan evidenced by that
certain Consolidated and Restated Promissory Note of even date herewith ("Note")
and secured  by,  among  other  things,  that  certain  Mortgage  Consolidation,
Assignment of Rents, Security Agreement and Fixture Filing of even date herewith
("Mortgage").  All capitalized terms used herein and not otherwise defined shall
have the same meanings ascribed to them in the Note and/or the Mortgage.

       Robert  F.  Gossett,  Jr.  (herein  referred  to as a  "Principal")  owns
indirectly  some of the general  partnership  interests and limited  partnership
interests in Borrower. It is in the direct financial interest and to the benefit
of  Principal  to execute and deliver  this letter  agreement  ("Agreement")  to
Lender  so as to  induce  Lender  to make  the  Loan to and for the  benefit  of
Borrower.  Accordingly,  Principal  agrees that Principal  shall,  together with
Borrower,  be  jointly  and  severally  personally  liable to pay the  following
(collectively the "Retained Liabilities"):

       (a)    all losses, damages, costs and expenses, including attorneys' fees
              and expenses, incurred by Lender as a result of:

              (i)    the  collection and receipt of proceeds and income from the
                     Property and the other assets and obligations  securing the
                     Loan by or for the  benefit of  Borrower  or any  Principal
                     following an Event of Default  which are not paid to Lender
                     or  applied  to the  Property  in the  ordinary  course  of
                     business;

              (ii)   fraud by  Borrower or by any partner or officer of Borrower
                     with a management role in Borrower;

              (iii)  material  misrepresentation by Borrower or any other person
                     or entity which is an officer of Borrower or any partner of
                     Borrower  with a  management  role in  connection  with the
                     Loan;


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              (iv)   misapplication or misappropriation of funds in which Lender
                     has a security  interest  which come into the possession of
                     Borrower or any Principal;

              (v)    intentional or material waste to the Property;

              (vi)   the breach of the  obligations  set forth in the  Hazardous
                     Substance   Indemnification  Agreement  from  Borrower  and
                     Principal  to Lender of even date  herewith,  as  hereafter
                     amended, if at all;

              (vii)  the breach of the  provisions  contained  in  Paragraph  15
                     (transfers  of  the  property  or  beneficial  interest  in
                     Borrower; assumption) of the Mortgage;

              (viii) the breach of the provisions  contained in Paragraph 16 (no
                     additional liens) of the Mortgage; or

              (ix)   the breach of the  provisions  contained  in  Paragraph  17
                     (single asset entity) of the Mortgage; and

       (b)    any claim for any  commissions  or brokerage  fees relating to the
              Loan.

       The foregoing shall in no way limit or impair the enforcement against the
Property  or any other  security  granted  by the Loan  Documents  of any of the
Lender's rights and remedies pursuant to the Loan Documents.

       Principal  agrees that the  liability  of  Principal  shall be direct and
immediate as a primary and not a secondary  obligation or liability,  and is not
conditional or contingent upon the pursuit of any remedies  against  Borrower or
any other person,  or against any collateral or liens held by Lender.  Principal
waives any rights  which it may have to require  that (a) Lender  first  proceed
against  Borrower,  or any other  person or entity with  respect to the Retained
Liabilities,  (b) Lender first proceed  against any collateral held by Lender or
(c) any party be joined in any proceeding to enforce the Retained Liabilities.

       Principal  agrees not to exercise  any rights to enforce any remedy which
Lender may have against Borrower,  any rights to participate in any security for
the Loan and any rights of indemnity, reimbursement, contribution or subrogation
which Principal may have against  Borrower or against any other person or entity
with respect to the Retained  Liabilities  until the Indebtedness of Borrower to
Lender under the Note and the Loan Documents has been satisfied in full.

       Principal  consents and agrees that Lender may at any time, and from time
to time,  without notice to or further consent from Principal and either with or
without consideration do any one or more of the following, all without affecting
the agreements  contained  herein or the liability of Principal for the Retained
Liabilities:  (a)  release  any  person  who may  hereafter  become a  Principal
hereunder;  (b) surrender without  substitution any property or other collateral
of any kind or nature  whatsoever  held by  Lender,  or by any  person,  firm or
corporation on Lender's behalf

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or for Lender's  account,  securing the Loan or the  Retained  Liabilities;  (c)
modify the terms of any document evidencing, securing or setting forth the terms
of the Loan; (d) grant releases, compromises and indulgences with respect to the
Loan or the  Retained  Liabilities  or any persons or entities  now or hereafter
liable  thereon;  or (e) take or fail to take any action of any type  whatsoever
with respect to the Loan or the Retained Liabilities.

       Principal hereby waives and agrees not to assert or take advantage of any
defense based upon:

       (a)    the  incapacity,   lack  of  authority,  death  or  disability  of
              Borrower, or any other person or entity;

       (b)    the failure of Lender to commence  an action  against  Borrower or
              any other  person or to proceed  against or exhaust  any  security
              held  by  Lender  at  any  time  or to  pursue  any  other  remedy
              whatsoever at any time;

       (c)    any duty on the part of Lender to disclose to Principal  any facts
              Lender may now or hereafter know regarding Borrower  regardless of
              whether   Lender  has  reason  to  believe  that  any  such  facts
              materially  increase the risk beyond that which Principal  intends
              to assume or has reason to believe  that such facts are unknown to
              Principal,  Principal  acknowledging  that it is fully responsible
              for being and keeping  informed  of the  financial  condition  and
              affairs of Borrower;

       (d)    lack of notice of  default,  demand  of  performance  or notice of
              acceleration  to Borrower,  or any other party with respect to the
              Loan or the Retained Liabilities;

       (e)    the consideration for this Agreement;

       (f)    any acts or omissions  of Lender which vary,  increase or decrease
              the risk on Principal;

       (g)    any statute of  limitations  affecting  the liability of Principal
              hereunder,  the  liability of Borrower or any  guarantor,  if any,
              under the Loan Documents, or the enforcement hereof, to the extent
              permitted by law;

       (h)    the  application  by  Borrower  of the  proceeds  of the  Loan for
              purposes other than the purposes represented by Borrower to Lender
              or intended or understood by Lender or Principal;

       (i)    an  election  of remedies  by Lender,  including  any  election to
              proceed   against  any   collateral  by  judicial  or  nonjudicial
              foreclosure,  whether real  property or personal  property,  or by
              deed in lieu  thereof,  and  whether  or not  every  aspect of any
              foreclosure  sale is commercially  reasonable,  and whether or not
              any such  election of remedies  destroys or otherwise  impairs the
              subrogation  rights of  Principal  or the rights of  Principal  to
              proceed against  Borrower or any guarantor for  reimbursement,  or
              both;

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       (j)    any statute or rule of law which provides that the obligation of a
              surety must be neither  larger in amount nor in any other  aspects
              more burdensome than that of a principal;

       (k)    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; and

       (l)    any  borrowing or any grant of a security  interest  under Section
              364 of the Federal Bankruptcy Code.

       Principal  covenants  and agrees to provide to Lender a draft copy of his
financial  statements  prepared in accordance with sound  accounting  principles
applied on a  consistent  basis,  certified  by such  Principal to be a true and
complete copy of such financial  statements and in form reasonably  satisfactory
to Lender, within sixty (60) days of the end of each calendar year, with a final
version of such final  statements  to be provided to Lender  within  ninety (90)
days of the end of each calendar year.

       PRINCIPAL AND LENDER HEREBY WAIVE THEIR RESPECTIVE RIGHTS TO A JURY TRIAL
OF ANY CLAIM OR CAUSE OF ACTION  BASED UPON,  OR ARISING OUT OF THIS  AGREEMENT.
PRINCIPAL AND LENDER  ACKNOWLEDGE  THAT THIS WAIVER IS A MATERIAL  INDUCEMENT TO
ENTER  INTO A  BUSINESS  RELATIONSHIP,  THAT EACH HAS  RELIED ON THIS  WAIVER IN
ENTERING INTO THIS  AGREEMENT AND THAT EACH WILL CONTINUE TO RELY ON THIS WAIVER
IN THEIR RELATED  FUTURE  DEALINGS.  PRINCIPAL AND LENDER  REPRESENT AND WARRANT
THAT EACH HAS HAD THE  OPPORTUNITY  TO REVIEW  THIS JURY  WAIVER  WITH ITS LEGAL
COUNSEL, AND THAT EACH KNOWINGLY AND VOLUNTARILY WAIVES ITS JURY TRIAL RIGHTS.

       Principal further agrees that the provisions of this Agreement shall bind
each Principal's heirs, personal representatives, successors and assigns, as the
case may be.

       Notwithstanding  anything in this  Agreement or in the Loan  Documents to
the  contrary,  Principal's  liability  hereunder,  including  for the  Retained
Liabilities,  shall  terminate if (a) Robert F. Gossett Jr. shall no longer be a
general  partner of  Corporate  Realty  Income Fund I, L.P.  and (b) a successor
general partner or another individual or entity acceptable to Lender in Lender's
reasonable discretion agrees to assume all of Principal's liabilities hereunder.

       This Agreement  shall be governed by, and shall be construed and enforced
in accordance  with, the internal laws of the State of Illinois,  without regard
to conflicts of law principles.


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       Principal  acknowledges  that Principal's  execution and delivery of this
Agreement to Lender is a material  inducement to Lender's  making of the Loan to
Borrower.

                                        PRINCIPAL:


                                        _____________________________
                                        Name: Robert F. Gossett, Jr.