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                                                                  Exhibit 10.163

                                    GUARANTY
                                 LOAN NO. 753946

     THIS GUARANTY (as the same may from time to time hereafter be modified,
supplemented or amended, the "GUARANTY") is made as of June 17, 2004 by INLAND
WESTERN RETAIL REAL ESTATE TRUST, INC., a Maryland corporation, having an office
at 2901 Butterfield Road, Oak Brook, Illinois 60523 ("GUARANTOR"), in favor of
PRINCIPAL LIFE INSURANCE COMPANY, an Iowa corporation, having a principal place
of business and post office address at c/o Principal Real Estate Investors, LLC,
801 Grand Avenue, Des Moines, Iowa 50392-1450 ("LENDER").

                                    RECITALS:

     Lender has agreed to make a loan (the "LOAN") in the original principal sum
of Twenty Eight Million Five Hundred Ten Thousand and No/100 Dollars
($28,510,000.00) (the "LOAN AMOUNT") to INLAND WESTERN ARVADA, L.L.C., a
Delaware limited liability company ("BORROWER"); and

     The Loan is evidenced by Borrower's secured promissory note made payable
and delivered to Lender (as the same may from time to time hereafter be
modified, amended, supplemented, extended or consolidated in writing, and any
note(s) issued in exchange therefor or replacement thereof, the "NOTE") and
further evidenced and secured by a "MORTGAGE" (it being agreed that "Mortgage"
as hereinafter used shall be construed to mean "mortgage" or "deed of trust" or
"trust deed" or "deed to secure debt" as the context so requires) on certain
real estate located in Jefferson County, Colorado, together with all existing
improvements constructed thereon, said Premises being more particularly
described in said Mortgage, and an Assignment of Leases ("ASSIGNMENT OF
LEASES"); and

     In connection with the Loan, the Borrower has also executed that certain
Environmental Indemnity ("ENVIRONMENTAL INDEMNITY") for the benefit of Lender
(the Note, Environmental Indemnity, Mortgage and Assignment of Leases and all
other instruments or agreements by which the Loan is evidenced or secured are
hereinafter collectively referred to as the "UNDERLYING INSTRUMENTS"); and

     It is a condition of Lender's agreement to make the Loan that Guarantor be
unconditionally liable for and personally guarantee the payment and performance
of certain liabilities and obligations of the Borrower under the Underlying
Instruments upon the terms and conditions as are hereinafter set forth; and

     WHEREAS, Guarantor is financially interested in Borrower and is materially
benefited by the consummation of the Loan and has agreed to unconditionally and
personally guarantee the payment and performance of certain liabilities and
obligations of Borrower under the Underlying Instruments upon the terms and
conditions as are hereinafter set forth.

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     NOW, THEREFORE, in order to induce Lender to make the Loan to Borrower,
Guarantor intending to be legally bound, hereby makes the following
representations and warranties to the Lender and hereby covenants and agrees
with the Lender as follows:

1.   Guarantor absolutely, irrevocably and unconditionally guarantees to the
     Lender payment and the full, faithful and timely performance of any and all
     liabilities and obligations of Borrower whether now existing or hereafter
     incurred under the Environmental Indemnity and paragraph 9 of the Note (all
     of which payments, liabilities and obligations are hereinafter collectively
     referred to as the "Guaranteed Obligations").

2.   Guarantor absolutely, irrevocably and unconditionally waives notice of
     acceptance of this Guaranty and notice of any payment, liability or
     obligation to which it may apply, and waives presentment, demand of
     payment, protest, notice of dishonor or nonpayment of such liabilities
     under this Guaranty or any of the Underlying Instruments creating the
     Guaranteed Obligations and any suit or taking other action by the Lender
     against, and any other notice to, any party liable thereon or any property
     which may be security therefor.

3.   The Lender may at any time and from time to time without the consent of, or
     notice to, Guarantor, without incurring any responsibility to Guarantor and
     without impairing or releasing any of the obligations of Guarantor
     hereunder, upon or without any terms or conditions and in whole or in part:

     (a)    renew, alter or change the interest rate, manner, time, place or
            terms of payment or performance of any of the Guaranteed
            Obligations, or any liability incurred directly or indirectly in
            respect thereof, whereupon the guaranty herein made shall apply to
            the Guaranteed Obligations as so changed, extended, renewed or
            altered;

     (b)    sell, exchange, release, surrender, and in any manner and in any
            order realize upon or otherwise deal with any property at any time
            directly and absolutely assigned or pledged or mortgaged to secure
            the Guaranteed Obligations or any liabilities (including any of
            those hereunder) incurred directly or indirectly in respect thereof;

     (c)    exercise or refrain from exercising any rights against Borrower or
            any other person (including Guarantor) or otherwise act or refrain
            from acting with regard to the Underlying Instruments, Guaranteed
            Obligations or this Guaranty;

     (d)    settle or compromise any of the Guaranteed Obligations, any security
            therefor or any liability (including any of those hereunder)
            incurred directly or indirectly in respect thereof or hereof, and/or
            subordinate the payment of all or any part thereof to the payment of
            any liability of Borrower (whether or not then due) to creditors of
            Borrower other than the Lender and Guarantor;

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     (e)    apply any sums in whatever manner paid or realized to any liability
            or liabilities of Borrower to the Lender regardless of what
            liability or liabilities of Borrower remain unpaid;

     (f)    consent to or waive any breach of or any act, omission or default
            under the Underlying Instruments or otherwise amend, modify or
            supplement any of such instruments or agreements; and/or

     (g)    sell, convey or assign, whether into a securitized transaction or
            otherwise, all or any part of Lender's interest in this Guaranty and
            the Underlying Instruments.

4.   (a)    No invalidity, irregularity or unenforceability of all or any part
            of the Underlying Instruments, the Guaranteed Obligations or this
            Guaranty, or of any security therefor, shall affect, impair or
            constitute a defense to this Guaranty. This Guaranty is a direct and
            primary obligation of Guarantor, and Guarantor's obligations
            hereunder are not as a surety. This is a guaranty of payment and
            performance, and not merely a guaranty of collection.

     (b)    Guarantor acknowledges and agrees that this Guaranty and Guarantor's
            obligations with respect to payments and performance under the
            Environmental Indemnity shall remain in full force and effect,
            notwithstanding the fact that the Note and payments due under the
            other Underlying Instruments have been paid in full.

5.   (a)    Notwithstanding any payment or payments made by Guarantor hereunder,
            Guarantor will not assert or exercise any right of the Lender or of
            such Guarantor against Borrower to recover the amount of any payment
            made by such Guarantor to the Lender by way of subrogation,
            reimbursement, contribution, indemnity or otherwise arising by
            contract or operation of law, and Guarantor shall not have any right
            of recourse to or any claim against assets or property of Borrower,
            whether or not the obligations of Borrower have been satisfied, all
            of such rights being herein expressly waived by Guarantor. The
            provisions of this paragraph shall survive the termination of this
            Guaranty, and any satisfaction and discharge of Borrower by virtue
            of any payment, court order or any applicable law.

     (b)    Notwithstanding the provisions of Section 5(a), Guarantor shall have
            and be entitled to all rights of subrogation otherwise provided by
            applicable law in respect of any payment Guarantor may make or be
            obligated to make under this Guaranty, and to assert and enforce the
            same, in each case on and after, but at no time prior to, the date
            (the "SUBROGATION TRIGGER DATE") which is 91 days after the date on
            which all obligations under the Underlying Instruments shall have
            been paid or performed in full, if and only if the existence of
            Guarantor's rights under this Section 5(b) would not make Guarantor
            a creditor (as defined in the Bankruptcy Reform Act of 1978, an
            amended, 11 U.S.C. Sections 101 et seq., and

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            the regulations adopted and promulgated pursuant thereto) of
            Borrower in any insolvency bankruptcy, reorganization or similar
            proceeding commenced on or prior to the Subrogation Trigger Date.

     (c)    In the event that Guarantor shall advance or become obligated to pay
            any sums with respect to any obligation hereby guaranteed or in the
            event that for any reason whatsoever the Borrower or any subsequent
            owner of the collateral securing the Loan is now, or shall hereafter
            become, indebted to Guarantor, Guarantor agrees that the amount of
            such sums and of such Indebtedness together with all interest
            thereon, shall at all times be subordinate as to the lien, time of
            payment and in all other respects, to all sums, including principal,
            interest and other Indebtedness, at any time owing to the Lender
            under any of the Underlying Instruments. Nothing herein contained is
            intended or shall be construed to give to Guarantor any right to
            participate in any way in the right, title or interest of the Lender
            in or to the collateral securing the Loan, notwithstanding any
            payments made by Guarantor under this Guaranty, all such rights of
            participation being hereby expressly waived and released.

6.   Guarantor agrees that to the extent that Borrower makes a payment or
     payments to Lender, which payment or payments or any part thereof are
     subsequently invalidated, declared to be fraudulent or preferential, set
     aside or required, for any of the foregoing reasons or for any other
     reasons, to be repaid or paid over to a custodian, trustee, receiver or any
     other party under any bankruptcy act, state or federal law, common law or
     equitable cause, then to the extent of such payment or repayment, the
     obligation or part thereof intended to be satisfied shall be revived and
     continued in full force and effect as if such payment had not been made.

7.   Guarantor makes the following representations and warranties which shall
     survive the execution and delivery of this Guaranty:

     (a)    Guarantor is and, until the Indebtedness is paid in full, will
            continue to (i) be a duly organized and validly existing entity in
            good standing under the laws of the state of its formation, (ii) be
            duly qualified as a foreign entity in each jurisdiction in which the
            nature of its business makes such qualification necessary or
            desirable, (iii) have the requisite power and authority to carry on
            its business as now being conducted, (iv) have the requisite power
            to execute, deliver arid perform its obligations under this
            Guaranty, and (v) comply with the provisions of all of its
            organizational documents, and the Legal Requirements of the state of
            its formation.

     (b)    The execution, delivery and performance of this Guaranty (i) are
            within the applicable powers of Guarantor; (ii) have been authorized
            by all requisite action; (iii) have received all necessary approvals
            and consents, corporate, governmental or otherwise; (iv) does not
            and will not violate, conflict with, result in a breach of

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            or constitute (with notice or lapse of time, or both) a default
            under any provision of law, any order or judgment of any court or
            governmental authority, the articles of incorporation, by-laws,
            partnership, operating or trust agreement, or other governing
            instrument of Guarantor, or any indenture, agreement or other
            instrument to which Guarantor is a party or by which Guarantor or
            any of Guarantor's assets is or may be bound or affected; (v) does
            not and will not result in the creation or imposition of any lien,
            charge or encumbrance whatsoever upon any of Guarantor's assets; and
            (vi) does not and will not require any authorization or license
            from, or any filing with, any governmental authority or other body.

     (c)    This Guaranty constitutes the legal, valid and binding obligations
            of Guarantor, enforceable against Guarantor in accordance with its
            terms, except as may be limited by (i) bankruptcy, insolvency,
            reorganization or other similar laws affecting the rights of
            creditors generally, and (ii) general principles of equity
            (regardless of whether considered in a proceeding in equity or at
            law).

8.   Guarantor and Borrower are separate and distinct entities with no identity
     of interest with respect to any Indebtedness which may become owed or any
     payments which may be made hereunder. Borrower is not contractually bound
     to Guarantor with respect to any payments hereafter made under this
     Guaranty in any manner which would have the effect of imputing the
     liability of Guarantor hereunder to Borrower.

9.   Guarantor is related and/or affiliated with Borrower, has personal
     knowledge of and is familiar with Borrower's business affairs, books and
     records and has the ability to influence Borrower's financial decisions.
     Guarantor represents that Borrower is in sound financial condition as of
     the date of this Guaranty.

10.  Nothing herein contained shall in any manner affect the lien or priority of
     the Mortgage, and upon the occurrence of an Event of a Default, the Lender
     may invoke any remedies it may have under the Underlying Instruments, or
     this Guaranty, either concurrently or successively and the exercise of any
     one or more of such remedies shall not be deemed an exhaustion of such
     remedy or remedies or a waiver of any other remedy or remedies and shall
     not be deemed an election of remedies. Guarantor hereby specifically waives
     any defense to its performance under this Guaranty based upon an election
     of remedies by Lender, including but not limited to an election to
     foreclose by nonjudicial sale under any deed of trust, or security
     agreement and pursue any other remedy which destroys, lessens or otherwise
     affects Guarantor's subrogation rights and/or its rights to reimbursement
     from or to proceed against Borrower or any other person, when resulting
     from the judicial or nonjudicial foreclosure (under any deed of trust, or
     security agreement) or the selling or otherwise disposing of or collecting
     or applying any property, real or personal, securing the Note, or
     otherwise. The exercise by the Lender of any such remedies shall not
     release or discharge Guarantor from its obligations hereunder unless and
     until the full amount of the Indebtedness evidenced by the Note and secured
     as aforesaid has been fully paid and

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     satisfied, and any such release or discharge shall be subject to the
     provisions of paragraph 4(b) hereof.

11.  This Guaranty shall remain in full force and effect until all obligations
     of the Borrower under the Underlying Instruments have been satisfied in
     full and are no longer subject to disgorgement under any applicable state
     or federal creditor rights or bankruptcy laws. No delay on the part of the
     Lender in exercising any options, powers or rights, or the partial or
     single exercise thereof, shall constitute a waiver thereof. No waiver of
     any rights hereunder, and no modification or amendment of this Guaranty,
     shall be deemed to be made by the Lender unless the same shall be in
     writing, duly signed on behalf of the Lender, and each such waiver (if any)
     shall apply only with respect to the specific instance involved and shall
     in no way impair the rights of the Lender or the obligations of Guarantor
     to the Lender in any other respect at any other time. This Guaranty and the
     rights and obligations of the Lender and of Guarantor hereunder shall be
     governed and construed in accordance with the laws of the state of
     Colorado, without regard to its conflicts of law principles and this
     Guaranty is binding upon Guarantor, Guarantor's heirs, personal
     representatives and permitted successors or assigns, and shall inure to the
     benefit of the Lender and its successors or assigns.

12.  Guarantor acknowledges that copies of the Underlying Instruments have been
     made available to Guarantor and that Guarantor is familiar with their
     contents. Guarantor affirmatively agrees that upon any Permitted Transfer
     effected in accordance with the provisions of the Underlying Instruments,
     it shall not be necessary for Guarantor to reaffirm its continuing
     obligations under this Guaranty, but Guarantor will do so upon request by
     Lender; provided, however, in the event a Permitted Transfer under items
     (ii) or (vi) of the Permitted Transfers occurs in compliance with the terms
     and conditions stated in the Mortgage, then Borrower may provide a
     substitute guarantor, acceptable to Lender in Lender's sole discretion, to
     assume the obligations of Guarantor under terms and conditions acceptable
     to Lender. Lender's approval of the substitute guarantor shall be deemed
     granted so long as such substitute guarantor is a Qualified Successor.

13.  GUARANTOR AND LENDER EACH KNOWINGLY, VOLUNTARILY AND INTENTIONALLY WAIVE,
     TO THE EXTENT PERMITTED BY LAW, TRIAL BY JURY IN ANY ACTIONS BROUGHT BY
     GUARANTOR OR LENDER IN CONNECTION WITH THIS GUARANTY, ANY OF THE LOAN
     DOCUMENTS, THE INDEBTEDNESS SECURED HEREBY, OR ANY OTHER STATEMENTS OR
     ACTIONS OF LENDER.

14.  Each notice, consent, request or other communication under this Guaranty
     (each a "Notice") which any party hereto may desire or be required to give
     to the other shall be deemed to be adequate and sufficient notice if given
     in writing and service is made by either (i) registered or certified mail,
     postage prepaid, in which case such notice shall be deemed to have been
     received three (3) business days following deposit to U.S. mail; or (ii)
     nationally recognized overnight air courier, next day delivery, prepaid, in
     which case

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     such notice shall be deemed to have been received one (1) business day
     following delivery to such nationally recognized overnight air courier. All
     Notices shall be addressed to Guarantor at its address given on the first
     page hereof, or to Lender at c/o Principal Real Estate Investors, LLC, 801
     Grand Avenue, Des Moines, Iowa 50392-1450, Attn: Commercial Real Estate
     Servicing, Loan No. 753946, or to such other place as any party may by
     notice in writing to the other parties designate as a place for service of
     notice.

15.  Each Guarantor (if more than one) whose signature appears below shall be
     deemed to be bound by the provisions of this Guaranty and the Guaranteed
     Obligations, whether each signature was affixed at the same or different
     times, and the term "Guarantor" as used herein shall be deemed to refer to
     each individually, as well as collectively, and each of the undersigned
     shall be jointly and severally liable for the Guaranteed Obligations
     hereunder, both personally and with recourse, irrespective of the recourse
     or non-recourse nature of the Underlying Instruments. Guarantor agrees that
     if this Guaranty is placed in the hands of an attorney for enforcement,
     Guarantor will reimburse Lender all expenses incurred, including attorney's
     fees.

16.  This Guaranty may be executed in counterparts, each of which shall be
     deemed an original; and such counterparts when taken together shall
     constitute but one agreement.

17.  Capitalized terms used herein and not otherwise defined shall have the
     meanings given to them in the Underlying Instruments.

     IN WITNESS WHEREOF, Guarantor has caused this Guaranty to be duly executed
and delivered as of the date first set forth above.

                     (REMAINDER OF PAGE INTENTIONALLY BLANK
                            SIGNATURES ON NEXT PAGE)

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                           SIGNATURE PAGE OF GUARANTOR
                                  TO GUARANTY

42-1579325
(Guarantor's Identification Number)


                                         INLAND WESTERN RETAIL REAL ESTATE
                                         TRUST, INC., a Maryland corporation


                                         By:      /s/ Valerie Medina
                                              -------------------------------
                                              Name:  Valerie Medina
                                                   --------------------------
                                              Title: asst. Secretary
                                                    -------------------------

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