<PAGE>

January26, 2000

High Equity Partners L.P. - Series 88
100 Jericho Quadrangle, Suite 214
Jericho, NY  11753-2727
         Attn: Mr. Peter Braverman



RE: Valuation Analysis for High Equity Partners L.P. - Series 88
    ("the Partnership")


Gentlemen:


By letter dated June 14, 2000, as amended by letters dated December 1, 2000 and
January 23, 2001, the Partnership retained Insignia/ESG, Inc. ("Insignia") to
undertake four separate valuation analyses with respect to the Partnership on
behalf of the Partnership. The engagement letter states that the Partnership
proposes to be converted (the "Transaction") into a real estate investment trust
(the "REIT") as described by the Partnership's management in Amendment No.5 to
the Registration Statement on Form S-4 of the REIT. We have assumed that in the
Transaction, each Partnership Unit would be exchanged for three REIT shares. In
each of the analyses, the value arrived at is expressed as an amount per
proposed REIT share. The following summarizes the specific analyses that the
Partnership asked us to perform.

1. An examination of the secondary market trading history ("Secondary Market
Trading History Analysis") of the existing units of limited partnership interest
in the Partnership (the "Partnership Units") on the limited secondary markets;

2. An analysis of the value of the net assets of the Partnership, and the amount
of cash available for distribution to partners, were the Partnership to
liquidate all of its real estate (the "Properties") and other assets
("Liquidation Analysis");

3. An analysis of the value of the Partnership Units, on a going concern basis,
based upon the future cash flow to be received by partners ("Going Concern
Analysis");

4. On the assumption that the Partnership was converted to the REIT, an analysis
of the expected range in which the REIT shares would trade based upon an
examination of comparable publicly traded real estate investment trusts
("Conversion and Comparable Company Analysis").

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In performing these analyses, we reviewed the documents provided to us by the
Partnership which are identified on Schedule A to this letter and we have relied
upon and assumed, without independent verification or investigation, the
accuracy and completeness of all financial and other information provided to or
discussed with us by the Partnership, its general partner and their respective
employees, representatives and affiliates. With respect to forecasts of the
future financial condition and operating results of the Partnership and the
proposed REIT provided to or discussed with us, we assumed, at the direction of
the management of the Partnership, without independent verification or
investigation, that such forecasts were reasonably prepared on bases reflecting
the best currently available information, estimates and good faith judgments of
the management of the Partnership. We have also relied upon assurances of the
management of the Partnership that they are unaware of any facts that would make
the historical information or forecasts incomplete or misleading. Except for the
appraisals provided to us by the Partnership referred to below, we have neither
made nor obtained any independent evaluations or appraisals of the assets or the
liabilities (contingent or otherwise) of the Partnership. The analyses do not
address the tax consequences of any aspect of the proposed Transaction (other
than transfer taxes assumed with the disposition of real estate upon
liquidation). We are not expressing any opinion as to the underlying evaluation,
future performance or long-term viability of the Partnership or the proposed
REIT, or the price at which Partnership Units or proposed REIT shares will
trade, whether or not the Transaction occurs. Our analyses are necessarily based
on the information available to us and general economic, financial and
securities market conditions and circumstances as they exist and can be
evaluated by us on the date hereof. It should be understood that, although
subsequent developments may affect our analyses, we do not have any obligation
to update, revise or reaffirm the analyses.

OVERVIEW OF CUSHMAN AND WAKEFIELD APPRAISAL METHODS

Insignia was provided with Cushman & Wakefield's ("Cushman") appraised values as
of June 30, 2000 for the Properties ("Appraised Values"). The valuation approach
selected by Cushman for the Properties varies based on each Property's
particular demise, encumbrances and the market conditions affecting it. With the
exception of the Properties identified as Tri-Columbus, Melrose Crossing II and
three Super Valu properties, Cushman employed a discounted cash flow approach
with, in most cases, support from the sales comparison approach.

Under the discounted cash flow approaches, the cash flows for the Properties for
the next 10 years were projected. At the end of the 10th year a terminal value
("Terminal Value") was added to the cash flow by capitalizing the projected 11th
year net operating income at a rate ("Appraised Cap Rate") selected by Cushman
and then deducting the anticipated costs associated with selling the Properties
("Selling Costs"). The cash flows were then discounted to present utilizing a
discount rate ("Appraised Discount Rate") selected by Cushman.

The values for Melrose Crossing II were determined based on the replacement cost
approach.


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The values for Tri-Columbus and three Super Valu properties were based on a
direct capitalization of income approach through which Cushman capitalized
estimated stabilized net operating income at the Appraised Cap Rate selected by
Cushman.

For the properties held through joint venture interests, Cushman provided a
second set of values ("Discounted J.V. Values") which contemplate a 25% to 35%
discount ("Joint Venture Discounts") to the Appraised Values in consideration of
the illiquidity associated with the ownership structure. The Discounted J.V.
Values together with the Appraised Values for the non-joint venture Properties
together constitute the Adjusted Appraisals ("Adjusted Appraisals").

1. SECONDARY MARKET TRADING HISTORY ANALYSIS

The Secondary Market Trading History Analysis is intended to value the
Partnerships based on the recent trading prices of Partnership Units. These
secondary markets cannot be characterized as either efficient or liquid markets,
and Partnership Units are expected to trade at a discount to liquidation value
or value based upon a going-concern analysis of the Partnership. The information
provided to us by the Partnership included the high sale price and low sale
price per Partnership Unit during each two months of trading from April 1, 1996
to August 31, 2000, together with a weighted average price per Partnership Unit
for the same period. The ranges of values indicated by this analysis are based
upon that secondary market trading data, with particular consideration given to
the weighted average trading prices in August and September, 2000, the most
recent period for which data was provided. Also considered are the trends in
prices over the period for which data was provided. The resulting range of
values per REIT share from the Secondary Market Trading History Analysis is
indicated to be $29.41 to $33.16 per share.

 2. LIQUIDATION ANALYSIS

The Liquidation Analysis is intended to value the Partnership's net assets
assuming a complete liquidation of the Partnership on a current basis. For
purposes of this analysis, we assumed that the non-joint venture Properties
would sell at their Appraised Values and that the interests in joint ventures
would sell at the values indicated in the Adjusted Appraisals.

The Liquidation Analysis assumes an adjustment for the anticipated property
disposition costs consisting of estimated transfer taxes, brokerage commissions
and closing costs ("Disposition Costs"). To the extent Properties were appraised
based on a discounted cash flow methodology, Disposition Costs were assumed to
be equal to Selling Costs utilized by Cushman in determining Terminal Value. For
Properties valued based on either a direct capitalization method or replacement
cost method, Disposition Costs were assumed to be 5% of Adjusted Appraisals.

Consideration was also given for the non-real estate assets of the Partnership.
The net assets considered were the Assets and Liabilities reported on the
Balance Sheet at


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September 30, 2000 included in the Form 10-Q of the Partnership for the period
ended September 30, 2000 and were included at the value set forth on the Balance
Sheet with the exception of the assets classified as Other Assets on the Balance
Sheets. The only Other Assets included were those that were deemed to have value
upon liquidation, i.e. furniture, fixtures & equipment and receivables.

The fee giveback obligation was also considered to be realized by the limited
partners of the Partnership at full value as of September 30, 2000.

Finally, consideration was given for the partnership dissolution costs that were
estimated at $500,000 for the Partnership.

No general partner liquidation fees or priority distributions were considered,
as the partnership liquidation values would not provide for same under the terms
of the Partnership Agreement.

The resulting range of values per proposed REIT share based on the Liquidation
Analysis is indicated to be $44.14 to $49.77 per share.

3. GOING-CONCERN ANALYSIS

Insignia was provided with the distribution history of the Partnership. In
addition, pro forma financial statements showing forecasts of Partnership cash
flows, expenses and potential distributions were also provided to us by the
Partnership for the period ending December 31, 2001.

The Going-Concern Analysis is intended to value the Partnership as a going-
concern assuming its current asset base. The most significant component of the
value of the Partnership as a going-concern is the distributions to the
partners, which are assumed to be equal to the cash flow from the Partnership's
real estate assets. For purposes of this analysis, the Properties' cash flows
were attributed values based on the Appraised Values.

An adjustment was made to give effect for the joint venture illiquidity that
would impact the Terminal Values of the joint venture Properties. This
adjustment was made for the joint venture Properties that were valued by Cushman
pursuant to the discounted cash flow methodology, by applying to the Terminal
Value the same Joint Venture Discount utilized by Cushman in determining the
appraised liquidation value and discounting it to the present utilizing the
Appraised Discount Rate. For joint venture Properties appraised under the direct
capitalization approach, an adjustment was made to give effect to the joint
venture illiquidity that would affect the implied Terminal Values of these
Properties. This value was then discounted to the present at 12%.

Consideration was also given for the non-real estate assets of the Partnership.
The net assets considered were the Assets and Liabilities cited on the Balance
Sheet as of September 30, 2000 included in the Form 10-Q of the Partnership for
the period ended



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September 30, 2000, and were included at the value set forth in the Balance
Sheet with the exception of the assets classified as Other Assets on the Balance
Sheet of the Partnership at September 30, 2000. The only Other Assets included
were those that were deemed to have value upon liquidation, i.e. furniture
fixtures & equipment and receivables.

An adjustment was also made to reflect the going-concern reserve requirements. A
general reserve of $1,000,000 was to be maintained by the Partnership and then
liquidated upon termination of the Partnership. An adjustment was thus made
equal to the cost of maintaining this reserve. The net cost was assumed to be
12% of the reserve per annum. A further adjustment was made for anticipated
capital expenditures at properties that were valued under either the replacement
cost or direct capitalization approaches, as no capital reserves were considered
in the appraisals for these properties. The reserves were based on actual
anticipated capital requirements over the next five years as estimated by the
management of the Partnership, and were discounted to present from the
anticipated date of expenditure utilizing a discount rate of 5%. A 5% discount
rate was selected as it is the approximate rate at which the reserved funds are
expected to earn interest.

Finally, an adjustment was made for the cost of asset management fees and
administrative costs. The values of these costs were derived by discounting the
anticipated annual cost of these expenses for the life of the Partnership. The
capitalization rates employed were equal to the weighted average Appraised
Discount Rate/Appraised Cap Rate for the Properties.

The resulting range of values per proposed REIT share based on the Going-Concern
Analysis is indicated to be $32.14 to $36.25 per share.

4. CONVERSION AND COMPARABLE COMPANY ANALYSIS

The Conversion and Comparable Company Analysis endeavors to determine the range
of values for the proposed REIT's shares.

The methodology employed in determining the REIT's range of values consisted of
applying the Projected Funds from Operations ("Projected FFO") of the REIT to a
range of multiples (the "FFO Multiples") which are consistent with the FFO
Multiples (based on projected funds from operations for 2001) at which
small-capitalization real estate investment trusts (those with an implied market
capitalization less than $250 million) were trading in the marketplace during
November 2000. Funds from operations were calculated in accordance with the
guidelines set out by the National Association of Real Estate Investment Trusts
("NAREIT"). While no directly comparable companies were identified, by adjusting
the median Projected FFO multiple for small-capitalization real estate
investment trusts a range of reasonable FFO Multiples for the REIT was
established. At your request, we limited the range of FFO Multiples for the REIT
to approximately 10% from the low multiple to the high multiple. The resulting
range of reasonable FFO Multiples for the REIT was determined to be 5.1 to 5.6.



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The Projected FFO of the REIT is comprised of two components: (1) Pro-forma FFO
("Pro-Forma FFO") for the assets currently owned ("Current Assets") by the
Partnership and (2) Anticipated FFO ("Anticipated FFO") for assets projected to
be acquired by the REIT in the future ("New Assets").

The Pro-Forma FFO is based on the actual operating results of the Current Assets
for the 12 month period ending September 30, 2000, as adjusted for the
anticipated increase in Asset Management Fees resulting from the higher Adjusted
Appraisals as compared to the 1998 appraised values.

Anticipated FFO is based on the projected operating results of the New Assets,
as decreased by the rise in the asset management fees resulting from the
acquisition of the New Assets. The New Assets are assumed to be acquired in two
ways: (1) by utilizing all available cash less a reserve equal to 3% of the
Adjusted Appraisals to buy New Assets and (2) by leveraging the Current Assets
and the New Assets to a level of 75% with debt which carries an interest rate of
8%. The New Assets are assumed to generate net operating income equal to 10.5%
of their gross purchase price. The resulting range of values per proposed REIT
share based on the Conversion and Comparable Company Analysis are indicated to
be $31.55 to $34.65 per share.

The information set forth in this letter does not constitute and should not be
construed as a recommendation to any holder of Partnership Units with respect to
the proposed Transaction. The analyses do not address the merits of the proposed
Transaction or consider any alternatives to the proposed Transaction. This
letter has been prepared for the Partnership, and should not be reproduced,
summarized, described or referred to without the prior written consent of
Insignia; provided, however, that this letter may be summarized and reproduced
in full in the Registration Statement on Form S-4 to be filed by the
Partnership.

                                         Insignia/ESG, Inc.


                                    By:  /s/ Kevin F. Haggerty
                                        ------------------------------
                                    Title: Executive Managing Director

                                    Name:  Kevin F. Haggerty




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                                   SCHEDULE A

LIST OF PARTNERSHIP-PROVIDED INFORMATION AND MATERIALS
<TABLE>
<CAPTION>
ITEM                                                    DESCRIPTION
----                                                    -----------
<S>                                                     <C>
Appraisals                                              Narrative  appraisals  of each of the  Partnership's
                                                        properties  prepared  by Cushman &  Wakefield  as of
                                                        June 30, 2000
------------------------------------------------------- -----------------------------------------------------
Forms 10-K                                              Form  10-K for the  Partnership  for the year  ended
                                                        December 31, 1999
------------------------------------------------------- -----------------------------------------------------
Forms 10-Q                                              Form 10-Q for the  Partnership for the quarter ended
                                                        September 30, 2000
------------------------------------------------------- -----------------------------------------------------
Capital Plans                                           Descriptions    of    the    anticipated     capital
                                                        improvements  requirements  at of the  Partnership's
                                                        properties for the next 5 years
------------------------------------------------------- -----------------------------------------------------
Asset Management Fees                                   The    Partnership's   and   the   proposed   REIT's
                                                        anticipated  asset  management  fees  based  on  the
                                                        Appraised Values
------------------------------------------------------- -----------------------------------------------------
Administrative Expenses                                 The Partnership's and the proposed REIT's
                                                        anticipated Administrative Costs based on historical
                                                        costs and management's estimation of future
                                                        costs assuming a 3% inflationary factor
------------------------------------------------------- -----------------------------------------------------
Pro-Forma                                               FFO A projection of the Partnership's and the
                                                        REIT's funds from operations based on the
                                                        assets currently owned by the Partnership.
------------------------------------------------------- -----------------------------------------------------
Anticipated FFO                                         A  projection  of the  increase in the REIT's  funds
                                                        from  operations  based  on the  acquisition  of New
                                                        Assets  assuming 75%  leverage of the  Partnership's
                                                        Current   Assets   and  New   Assets,   and  use  of
                                                        approximately 80% of the Partnership's  current cash
                                                        reserves   for  the   acquisition   of  New  Assets.
                                                        Leverage was assumed to be 75% and bear  interest at
                                                        an average  rate of 8%, and New Assets were  assumed
                                                        to generate net  operating  income of 10.5% of their
                                                        gross cost.  Asset  Management  Fees were assumed to
                                                        be based upon 1.25%
------------------------------------------------------- -----------------------------------------------------


                                                   7
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ITEM                                                    DESCRIPTION
----                                                    -----------
                                                        of the prospective  value of the New Assets.
------------------------------------------------------- -----------------------------------------------------
Excess Cash Distribution                                Excess cash distribution equals
                                                        cash on hand less projected capital
                                                        improvements and reserves.
------------------------------------------------------- -----------------------------------------------------
Projected FFO                                           The total FFO assumed to be generated
                                                        by the proposed REIT in the future. Calculated
                                                        by adding the Pro-Forma FFO and Anticipated FFO.
------------------------------------------------------- -----------------------------------------------------
Going-Concern Reserve Requirements                      An estimate of the cost of
                                                        the maintenance and use of the cash reserves
                                                        projected for the Partnership assuming the
                                                        proposed REIT conversion does not occur.
------------------------------------------------------- -----------------------------------------------------
Form S-4                                                Amendment  No. 5 to the  Registration  Statement  on
                                                        Form S-4 filed by the REIT in January 2001.
------------------------------------------------------- -----------------------------------------------------
Pro-Forma Partnership Income Statements                 Pro-forma   stabilized  income  statements  for  the
                                                        Partnership  assuming the proposed  REIT  conversion
                                                        does   not   occur.    These   statements    reflect
                                                        operations   for  the  twelve   month  period  ended
                                                        September  30,  2000 as  adjusted  for  major  known
                                                        changes  in  property  operations,  changes  in  the
                                                        Asset   Management   Fees  based  on  the  increased
                                                        Appraised  Going-  Concern  Values,   and  increased
                                                        administrative   costs   assuming  an   inflationary
                                                        factor of 3%.
------------------------------------------------------- -----------------------------------------------------
Secondary Market Trading History                        Chart of number and prices of Partnership
                                                        Units sold from April 1, 1996 through
                                                        September 30, 2000 as reported by Partnership Spectrum.
------------------------------------------------------- -----------------------------------------------------
Fee Giveback Obligations                                The General Partner's current fee giveback
                                                        obligations stipulated in The Class Action
                                                        Settlements, as defined in the Form S-4.
------------------------------------------------------- -----------------------------------------------------
Going Concern Distributions                             Estimates of the distributions by the Partnership if the
                                                        Partnership were to be a going concern.
------------------------------------------------------- -----------------------------------------------------
Partnership Dissolution Costs                           Estimates of the Partnership-level costs associated
                                                        with the dissolution and winding up of the
                                                        affairs of the Partnership.
------------------------------------------------------- -----------------------------------------------------
</TABLE>




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