Exhibit
10
   AMENDMENT NO. 3 TO CREDIT
AGREEMENT
  THIS
AMENDMENT NO. 3 TO CREDIT AGREEMENT (this “Amendment”) is dated
as of June __, 2008, by and among Cornerstone Operating Partnership, L.P., a
Delaware limited partnership (the “Administrative Borrower”), each of the
“Borrowing Base Subsidiaries” party hereto (together with the Administrative
Borrower, each a “Borrower” and collectively, “Borrowers”), the “Guarantors”
signatory hereto (together with Borrowers, the “Credit Parties”), HSH Nordbank
AG, New York Branch, a German banking corporation acting through its New York
branch, as lender (together with its successors and assigns, each a “Lender” and
collectively the “Lenders”), and HSH Nordbank AG, New York Branch, a German
banking corporation acting through its New York branch, in its capacity as
administrative agent for the Lenders (in its capacity as administrative agent
for the Lenders, together with any permitted successor administrative agent, the
“Administrative Agent”) and arranger.  Capitalized terms not defined
herein shall have the respective meanings set forth in the Credit Agreement (as
defined below).
  Recitals
  WHEREAS,
Borrowers, Guarantors, Lenders and Administrative Agent have entered into that
certain Credit Agreement dated as of June 30, 2006 (the “Original Credit
Agreement”), as amended by that certain Amendment and Waiver No. 1 to Credit
Agreement, dated as of July 31, 2007 (the “First Amendment”) and that certain
Amendment No. 2 to Credit Agreement, dated as of November 14, 2007 (the “Second
Amendment”, together with the Original Credit Agreement,  and the
First Amendment, and as otherwise modified or supplemented from time to time,
collectively, the “Credit Agreement”);
  WHEREAS,
pursuant to (i) that certain Joinder and Amendment Agreement dated as of
November 30, 2006, among COP-Goldenwest, LLC, a California limited liability
company (“COP-Goldenwest”), Administrative Borrower, the Guarantors, Lenders and
Administrative Agent, (ii) that certain Joinder Agreement dated as of November
30, 2006, among, COP-Western Ave., LLC a California limited liability company
(“COP-Western”), COP-Goldenwest, Administrative Borrower, the Guarantors,
Lenders and Administrative Agent, (iii) that certain Joinder Agreement dated as
of January 19, 2007, among COP-Deer Valley, LLC, an Arizona limited liability
company (“COP-Deer Valley”), COP-Western, COP-Goldenwest, Administrative
Borrower, the Guarantors, Lenders and Agent, and (iv) that certain Joinder
Agreement dated as of September 28, 2007, among COP-Pinnacle Peak, LLC, an
Arizona limited liability company (“COP-Pinnacle Peak”), COP-Western,
COP-Goldenwest, COP-Deer Valley, Administrative Borrower, the Guarantors,
Lenders and Agent, each of COP-Goldenwest, COP-Western, COP-Deer Valley and
COP-Pinnacle Peak were joined to the Credit Agreement and the other Financing
Documents, each as a “Borrower” and as a “Borrowing Base
Subsidiary.”
  WHEREAS,
the payment of the Obligations and the performance of the other obligations of
Borrowers under the Credit Agreement and the other Financing Documents are
secured by, amongst other things, (i) that certain Deed of Trust, Assignment of
Leases and Rents, Fixture Filing and Security Agreement, by COP-Goldenwest, as
grantor, in favor of Commonwealth Land Title Company, solely as trustee, for the
benefit of Administrative Agent, recorded as of December 1, 2006 in the Official
Records of Orange County, California, as Instrument No. 2006000808373 (the
“Goldenwest Deed of Trust), (ii) that certain Assignment of Leases and Rents, by
COP-Goldenwest, in favor of Administrative Agent, recorded as of December 1,
2006 in the Official Records of Orange County, California, as Instrument No.
2006000808374 (the “Goldenwest Assignment”), (iii) that certain Deed of Trust,
Assignment of Leases and Rents, Fixture Filing and Security Agreement, by
COP-Western, as grantor, in favor of Commonwealth Land Title Company, solely as
trustee, for the benefit of Administrative Agent, recorded as of December 1,
2006 in the Official Records of Los Angeles County, California, as Instrument
No. 2006266762 (the “Western Deed of Trust), (iv) that certain Assignment of
Leases and Rents, by COP-Western, in favor of Administrative Agent, recorded as
of December 1, 2006 in the Official Records of Los Angeles County, California,
as Instrument No. 20062667663 (the “Western Assignment”), (v) that certain Deed
of Trust, Assignment of Leases and Rents, Fixture Filing and Security Agreement,
by COP-Deer Valley, as grantor, in favor of Magnus Title Agency, solely as
trustee, for the benefit of Administrative Agent, recorded as of January 22,
2007 in the Official Records of Maricopa County, Arizona, as Instrument No.
20070081545 (the “Deer Valley Deed of Trust”), (vi) that certain Assignment of
Leases and Rents, by COP-Deer Valley, in favor of Administrative Agent, recorded
as of January 22, 2007 in the Official Records of Maricopa County, Arizona, as
Instrument No. 20070081546 (the “Deer Valley Assignment”), and (vii) that
certain Deed of Trust, Assignment of Leases and Rents, Fixture Filing and
Security Agreement, by COP-Pinnacle Peak, as grantor, in favor of Lawyers Title
Insurance Corporation, solely as trustee, for the benefit of Administrative
Agent, recorded as of October 2, 2007 in the Official Records of Maricopa
County, Arizona, as Instrument No. 20071083931 (the “Pinnacle Peak Deed of
Trust) and (viii) that certain Assignment of Leases and Rents, by COP-Pinnacle
Peak, in favor of Administrative Agent, recorded as of October 2, 2007 in the
Official Records of Maricopa County, Arizona, as Instrument No. 20071083932 (the
“Pinnacle Peak Assignment”).  The Goldenwest Deed of Trust, the
Western Deed of Trust, the Deer Valley Deed of Trust and the Pinnacle Peak Deed
of Trust hereafter collectively the “Existing Deeds of Trust”.  The
Goldenwest Assignment, the Western Assignment, the Deer Valley Assignment and
the Pinnacle Peak Assignment hereafter collectively the “Existing
Assignments.”
  
  NOW
THEREFORE in consideration of the promises and mutual covenants contained
herein, the parties hereto agree as follows:
  1.   Amendments.  Upon
satisfaction of all of the conditions of effectiveness set forth in Section 2
below, the following amendments shall take effect:
  1.1       Definitions.  The
following definitions are added to and made a part of Section 1.01 of the Credit
Agreement:
  ““Cash or Cash
Equivalents” means (i) cash, (ii) marketable securities issued or
directly and fully guaranteed or insured by the United States or any agency or
instrumentality thereof (provided, that the full faith and credit of the United
States is pledged in support thereof) having maturities of not more than one (1)
year from the date of acquisition, (iii) time deposits and certificates of
deposit of any commercial bank having, or which is the principal banking
subsidiary of a bank holding company organized under the laws of the United
States or any State thereof having, capital, surplus and undivided profits
aggregating in excess of $200,000,000, with maturities of not more than one (1)
year from the date of acquisition by REIT, (iv) commercial paper issued by any
Person incorporated in the United States rated at least A-1 or the equivalent
thereof by Standard & Poor’s Corporation or at least P-1 or the equivalent
thereof by Moody’s Investors Service, Inc. and in each case maturing not more
than one (1) year after the date of acquisition by REIT and (v) investments in
money market or mutual funds substantially all of whose assets are comprised of
securities of the types described in clauses (i) through (iv) above, in each
case, which are owned by REIT on an individual basis (as opposed to being owned
jointly with any other Person).
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  “Unencumbered Cash or Cash
Equivalents” means Cash or Cash Equivalents that have not been pledged to
any Person as security for any obligation of Guarantor or any other
Person.”
  1.2       Cash or Cash
Equivalents.  The following language is added to and made a
part of the Credit Agreement as Section 5.16:
  “Section
5.16.      Cash of Cash
Equivalents.  REIT shall, at all times, maintain Unencumbered
Cash or Cash Equivalents of not less than $5,000,000, measured as of the last
day of each calendar quarter based upon the certificate to be provided by
Administrative Borrower pursuant to Section 5.01(e)(iv) hereof.”
  1.3       Financial
Reporting.  Section 5.01(e) of the Credit Agreement is hereby
deleted and replaced its entirety with the following:
  “(e)     Promptly
after the preparation thereof, and no later than sixty (60) days after the last
day of each calendar quarter, (i) computations of Borrowing Base Net Operating
Income for each Borrowing Base Property, (ii) Debt Service Coverage Ratio as of
the last day of such calendar quarter, (iii) a Borrowing Base Certificate
executed by a Financial Officer of the Administrative Borrower setting forth its
computation of the Borrowing Base Loan Amount as of the last day of such
calendar quarter for such calendar quarter and (iv) a certificate executed by a
Financial Officer of REIT certifying the amount of Unencumbered Cash or Cash
Equivalents maintained by REIT, which certificate shall be in detail, scope and
presentation acceptable to Administrative Agent, in its sole
discretion.  The Administrative Agent shall notify the Administrative
Borrower in writing of any calculation errors or other errors in the calculation
of Borrowing Base Net Operating Income required by the Administrative Agent
pursuant to the definition of “Borrowing Base Net Operating
Income” herein and any corresponding adjustments to the Borrowing Base
Loan Amount (if any).”
  2.   Effectiveness of this
Amendment. The amendments set forth in Section 1 above shall not be
effective or binding (without affecting the other provisions of this Amendment)
until the following conditions have been satisfied or waived in writing by
Administrative Agent, in Administrative Agent’s sole and absolute discretion
(the date on which all such conditions being satisfied or waived, the “Effective
Date”):
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  2.1       Execution of
Documents.  Administrative Agent shall have received each of
the following documents (collectively the “Transaction
Documents”) duly executed and delivered by each of the parties
thereto:
  (a)       this
Amendment; and
  (b)       such
other documents and instruments requested by Administrative Agent.
  2.2       Title Updates. Administrative
Agent shall have obtained, at Borrowers’ expense, such new lender’s title
policies or modification, date-down or other endorsements to Lenders’ existing
title policies as Administrative Agent may require to insure the continued
validity of the Existing Deeds of Trust, as amended, and their, respective,
continuing first lien priority on each of the Borrower Base Properties, subject
of the Existing Deeds of Trust, over all encumbrances not previously approved in
writing by Administrative Agent.
  2.3       No Defaults.  As of
the Effective Date no Default or Event of Default shall have occurred and be
continuing.
  2.4       Payment of
Expenses.  Borrowers shall have paid to Administrative Agent
all costs and expenses incurred in connection with this Amendment as provided in
Section 7 hereof.
  2.5       Representations and
Warranties.  The representations and warranties of the Credit
Parties set forth in Section 3 of this Amendment shall be true and correct in
all material respects on and as of the Effective Date; provided that any
such representations and warranties that by their express terms are made as of a
specific date shall be true and correct in all material respects as of such
specific date.
  3.   Representations and
Warranties.  To induce Lenders and Administrative Agent to
enter into this Amendment, the Credit Parties hereby represent and warrant
that:
  3.1       The
execution, delivery and performance by each Credit Party of this Amendment, the
other Transaction Documents, and any other documents in connection herewith, or
therewith, to which it is a party are (a) within its powers and have been duly
authorized by all necessary action, (b) require no action by or in respect of,
or filing with, any Governmental Authority, any property manager or other third
party, (c) do not contravene, or constitute a breach of or default under, any
provision of applicable law or regulation, any of its constitutive documents or
of any judgment, injunction, order, decree, permit, license, note, mortgage,
agreement or other instrument binding upon such Person or any of its
Subsidiaries or their respective assets and (d) do not result in the creation or
imposition of any Lien on any asset of any Credit Party or any of its
Subsidiaries.
  3.2       This
Amendment, the other Transaction Documents and such other documents and
instruments executed by such Credit Party in connection herewith, or therewith,
have been duly executed and delivered by each Credit Party and constitutes a
valid and binding agreement of each Credit Party, in each case enforceable in
accordance with their respective terms, except as the enforceability thereof may
be limited by bankruptcy, insolvency, reorganization or moratorium or other
similar laws relating to the enforcement of creditors’ rights generally and by
general equitable principles.
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  3.3       Each
of the representations and warranties contained in Article III of the Credit
Agreement, as modified herein, is true and correct as of the date hereof, as
though made on, and as of, the date hereof.
  4.   Ratification of Credit
Agreement.  Except as specifically amended hereby, the terms
and conditions of the Credit Agreement and the other Financing Documents are in
all respects ratified and confirmed and remain in full force and
effect.
  5.   Governing
Law.   THIS AMENDMENT, IN ACCORDANCE WITH SECTION 5-1401
OF THE GENERAL OBLIGATION LAW OF THE STATE OF NEW YORK, SHALL BE CONSTRUED IN
ACCORDANCE WITH AND GOVERNED BY THE LAWS OF THE STATE OF NEW YORK WITHOUT REGARD
TO ANY CONFLICTS OF LAWS PRINCIPLES THEREOF THAT WOULD CALL FOR THE APPLICATION
OF THE LAWS OF ANY OTHER JURISDICTION, as more fully set forth in Section 9.09
of the Credit Agreement, which Section 9.09 is incorporated herein mutatis mutandisas though
set forth herein in full.
  6.   Compliance,
Release.  As additional consideration for Administrative Agent
and Lenders to enter into this Amendment, the Credit Parties hereby acknowledge
and agree that, as of the date of this Amendment: (i) Administrative Agent and
Lenders have fully complied with all of their respective obligations under the
Financing Documents, (ii) the Credit Parties have no knowledge of any act or
omission on the part of Administrative Agent or Lenders that constitutes a
default by Administrative Agent or Lenders under any of the Financing Documents
(or that, with the giving of notice, the passage of time, or both, would
constitute a default by the Administrative Agent or Lenders thereunder), (iii)
the Credit Parties have no knowledge of any fact or circumstance that would
prevent or prohibit Administrative Agent or Lenders from enforcing the Financing
Documents, and (iv) the Credit Parties have no claims, demands, damages, suits,
cross-complaints, causes of action or debts of any kind or nature whatsoever
that can be asserted to reduce or eliminate all or any portion of its obligation
to repay the Loans or to seek any affirmative relief from Administrative Agent
or Lenders with respect to the Loans or the Borrowing Base
Properties.  The Credit Parties hereby release and forever discharge,
and agree to indemnify, defend and hold harmless, Administrative Agent and
Lenders and their respective agents, servants, employees, directors, officers,
trustees, beneficiaries, attorneys, branches, affiliates, subsidiaries,
successors and assigns, of and from all damages, losses, claims, demands,
liabilities, obligations, actions, suits and causes of action whatsoever, that
the Credit Parties may now have or claim to have against Administrative Agent or
Lenders as of the date of this Amendment, and whether presently known or
unknown, and of every nature and extent whatsoever, on account of or in any way
concerning or arising out of the Borrowing Base Properties or the Loans, or
founded upon any of the Financing Documents, including, but not limited to, all
such loss or damage of any kind heretofore sustained or that may arise as a
consequence of the dealings between the parties up to and including the date of
this Amendment.  The Credit Parties acknowledge and agree that this
release is intended to extend to claims they do not know or suspect to
exist
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  7.   Payment of Administrative
Agent’s and Lenders’ Expenses.  Borrowers agree to reimburse
Administrative Agent and Lenders for all out-of-pocket expenses incurred by
Administrative Agent and Lenders in connection with the drafting, negotiation,
execution, delivery and performance of this Amendment and all related documents,
including, but not limited to, attorneys’ fees and costs incurred by
Administrative Agent and Lenders, premiums for any necessary new title policy or
endorsements to Lenders’ existing title policies, appraisal fees, cost analysis,
recording charges, escrow fees and all other costs.
  8.   Counterparts; Integration;
Effectiveness.  This Amendment may be executed in counterparts
(and by different parties hereto on different counterparts), each of which shall
constitute an original, but all of which when taken together shall constitute a
single contract.  This Amendment, and the other Financing Documents
constitute the entire contract among the parties relating to the subject matter
hereof and supersede any and all previous agreements and understandings, oral or
written, relating to the subject matter hereof.  Except as provided in
Section 3 hereof, this Amendment shall become effective when it shall have been
executed by the Administrative Agent and when the Administrative Agent shall
have received counterparts hereof which, when taken together, bear the
signatures of each of the other parties hereto.  Delivery of an
executed counterpart of a signature page of this Amendment by telecopy shall be
effective as delivery of a manually executed counterpart of this
Amendment.
   Signatures
on the following page.
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  IN
WITNESS WHEREOF, the parties hereto have executed and delivered this Amendment
as of the date first set forth above.
  “BORROWERS”CORNERSTONE
      OPERATING PARTNERSHIP, L.P.By:
                        Cornerstone
      Core Properties REIT, Inc.its
      General PartnerBy:Name:Title:COP-GOLDENWEST,
      LLCBy:
                        Cornerstone
      Operating Partnership, L.P.its
      sole MemberBy:
                        Cornerstone
      Core Properties REIT, Inc.its
      General PartnerBy:Name:Title:COP-WESTERN
      AVE., LLCBy:
                        Cornerstone
      Operating Partnership, L.P.its
      sole MemberBy:
                        Cornerstone
      Core Properties REIT, Inc.its
      General PartnerBy:Name:Title:
 
 signature
page continues
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  COP-DEER
      VALLEY, LLCBy:
                                Cornerstone
      Operating Partnership, L.P.its
      sole MemberBy:
                                Cornerstone
      Core Properties REIT, Inc.its
      General PartnerBy:Name:Title:COP-PINNACLE
      PEAK, LLCBy:
                                Cornerstone
      Operating Partnership, L.P.its
      sole MemberBy:
                                Cornerstone
      Core Properties REIT, Inc.its
      General PartnerBy:Name:Title:“GUARANTORS”
      and “RECOURSE LIABILITY PARTY”CORNERSTONE
      CORE PROPERTIES REIT, INC.By:Name:Title:CORNERSTONE
      REALTY ADVISORS, LLCBy:Name:Title:By:Name:Title:
  signature
page continues
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  “ADMINISTRATIVE
      AGENT”HSH
      NORDBANK AG, NEW YORK BRANCHBy  :Name:Title:By  :Name:Title:“LENDERS”HSH
      NORDBANK AG, NEW YORK BRANCHBy  :Name:Title:By  :Name:Title:
 
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