Document:

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                                                                   EXHIBIT 10.20

                                    GUARANTEE

      THIS GUARANTEE is entered into as of the 30th day of September, 2003 and
is made by the undersigned (the "Guarantor") in favor of Brookdale Senior
Housing, LLC, a Delaware limited liability company ("Buyer").

      WHEREAS, pursuant to that certain Real Estate Purchase Agreement dated as
of September 19, 2003 (the "Agreement") between AH PENNSYLVANIA OWNER LIMITED
PARTNERSHIP, an Ohio limited partnership, (the "Seller"), as seller, and the
Buyer, as buyer in which Buyer did agree to buy and Seller did agree to sell
that certain property located at 1050 McNeilly Road in the City of Mount
Lebanon, County of Allegheny, State of Pennsylvania (the "Property"); and

      WHEREAS, in order to induce Buyer to enter into the Agreement, the
Guarantor has agreed to guarantee the performance of Seller's obligations under
the Agreement.

      NOW THEREFORE, in consideration of the foregoing, and of the terms and
provisions set forth below, and other good and valuable consideration, the
receipt and sufficiency of which is hereby acknowledged, the parties do hereby
agree as follows:

      1. Guarantor hereby, unconditionally and irrevocably, guarantees to Buyer
and its respective members the full, prompt and faithful performance of Seller's
Obligations. If Seller shall become the debtor under the Federal Bankruptcy Code
or the subject of any other state or federal bankruptcy, insolvency or similar
proceeding, the same shall not affect the liability of any Guarantor hereunder.

      2. Upon the failure of Seller to meet Seller's obligations, Guarantor
shall, within five (5) business days from the date notice of such failure is
given to Guarantor, cure such failure. If any such failure to perform shall not
be cured by Guarantor within said five (5) business day period, Buyer may, at
its option, cure such all failures to perform Seller's obligations, including
the payment of any and all costs outstanding which were part of Seller's
obligations.

      3. Guarantor hereby waives absolutely and irrevocably any right of
subrogation to Buyer's claims against Seller and any right of indemnity,
reimbursement or contribution from Seller with respect to any payment made or
performance undertaken by Guarantor pursuant hereto.

      4. Without limiting or lessening the liability of the Guarantor under this
Guarantee, Buyer may, without notice to the Guarantor,

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      (a)   grant extensions of time or any other indulgences on Seller's
            obligations; and

      (b)   accept or make other arrangements with Seller and otherwise deal
            with Seller or other parties as Buyer may deem expedient.

      5. This Guarantee shall be a continuing guarantee, shall not be revoked by
death, shall inure to the benefit of, and be enforceable by, any successor or
assign of Buyer and shall be binding upon, and enforceable against, the
Guarantor and its successors and assigns.

      6. Except as expressly provided herein or in the Agreement, all additional
demands, presentments, notices of protest and dishonor, and notices of every
kind and nature, including those of any action or no action on the part of
Seller or Buyer are expressly waived by Guarantor. This is a guarantee of
payment and not of collection. Except as expressly provided herein or in the
Agreement, Guarantor hereby waives the right to require Buyer to proceed against
Seller or any other party and waives the right to require Buyer to pursue any
other remedy for the benefit of the Guarantor.

      7. Guarantor agrees to pay reasonable attorneys' fees and all other
reasonable costs and expenses which may be incurred in the enforcement of this
Guarantee after the failure of Guarantor to cure within the five (5) business
day time period as provided in paragraph 2 above.

      8. Any notice or demand hereunder shall be in writing, may be delivered
personally or sent by certified mail with postage prepaid or by reputable
courier service with charges prepaid, or, if to Buyer, by telecopier whereby the
receipt thereof may be confirmed. Any notice sent to the Guarantor shall be
addressed to the Guarantor at the address set forth below or such other address
in the United States of America as the Guarantor shall designate in a notice
given to Buyer in the manner described herein. Any notice sent to Buyer shall be
addressed to the attention of the Real Estate Investment Department at 720 East
Wisconsin Avenue, Milwaukee, WI 53202 and shall refer to NML JV No. 333313 and,
if telecopied, shall be telecopied to 414/665-1557, or at such other address or
telecopier number as Buyer shall designate in a notice given in the manner
described herein. Any notice or demand sent hereunder by telecopier shall also
be sent by regular U.S. mail, certified mail or reputable courier service. Any
notice or demand hereunder shall be deemed given when received. Any notice or
demand which is rejected, the acceptance of delivery of which is refused or
which is incapable of being delivered on a business day for any cause occasioned
by the addressee at the address or telecopier number specified herein or such
other address or telecopier number as may be designated pursuant hereto shall be
deemed received as of the date of attempted delivery.

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Mailing Addresses:

Brookdale Living Communities, Inc.
330 North Wabash Avenue, Suite 1400
Chicago, IL 60611

         GUARANTOR: AH PENNSYLVANIA OWNER LIMITED
                    PARTNERSHIP, an Ohio limited partnership

                    By: AH PENNSYLVANIA CGP, INC.,
                        an Ohio corporation, its general partner

                        By: /s/ R. Stanley Young
                            ----------------------------------
                        Name: R. Stanley Young
                        Its: Vice President

                    By: AH PENNSYLVANIA SUBORDINATED, LLC, an
                        Ohio limited liability company, its limited partner

                        By: /s/ R. Stanley Young
                            ----------------------------------
                        Name: R. Stanley Young
                        Its: Vice President<PAGE>

                                                                   EXHIBIT 10.21

LOAN NO. C-332847

                  SOUTHFIELD GUARANTEE OF RECOURSE OBLIGATIONS
                               (Single Guarantor)

      In consideration of the benefits which the undersigned (herein called
"Guarantor") will receive as a result of The Northwestern Mutual Life Insurance
Company, a Wisconsin corporation, ("Lender") making the above-numbered loan to
Brookdale Senior Housing, LLC, a Delaware limited liability company,
("Borrower") evidenced by a promissory note (the "Note") of even date herewith
in the original principal amount of $30,355,000.00 and secured by that certain
Southfield First Mortgage and Security Agreement of even date herewith executed
by Borrower, and that certain Devonshire First Open-End Mortgage and Security
Agreement of even date herewith executed by Borrower (collectively, the "Lien
Instrument") covering property in Oakland County, Michigan, and Allegheny
County, Pennsylvania (collectively the "Property"), and as an inducement
required by Lender to fund said loan, Guarantor has agreed to guarantee:

      (A)   A portion of the Recourse Obligations (as such term is defined in
            paragraph 9 hereof); and,

      (B)   Following the occurrence of a Triggering Event (as such term is
            defined in paragraph 9 hereof), the payment of the Note and all
            amounts at any time owed to Lender under the other Loan Documents
            (as hereinafter defined) and the performance of all terms, covenants
            and conditions in the Loan Documents.

      1. Therefore, for value received, Guarantor hereby, unconditionally and
irrevocably, guarantees to Lender and its successors and assigns the full,
prompt and faithful payment of twenty-five percent (25%) of all of the Recourse
Obligations, (i) notwithstanding any invalidity of, or defect or deficiency in
any Loan Documents, (ii) notwithstanding the fact that Borrower may have no
personal liability for all or a portion of the Indebtedness and Lender's
recourse against Borrower and Borrower's assets may be limited, and (iii)
notwithstanding any act, omission or thing which might otherwise operate as a
legal or equitable discharge of Guarantor. Guarantor shall, within five business
days from the date notice is given to Guarantor that any of the Recourse
Obligations is due and owing, pay such Recourse Obligation.

      "Loan Documents" means the Note, the Lien Instrument, that certain Loan
Commitment dated of even date herewith between Borrower and Lender, this
Southfield Guarantee of Recourse Obligations, that certain Devonshire Guarantee
of Recourse Obligations dated of even date herewith from Brookdale Living
Communities, Inc. to Lender, that certain (i) Southfield Absolute Assignment of
Leases and Rents of even date herewith between Borrower and Lender and (ii)
Devonshire Absolute Assignment of Leases and Rents of even date herewith between
Borrower and Lender (collectively, the "Absolute

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Assignment"), that certain Brookdale Living Communities, Inc. Certification of
even date herewith, that certain Limited Liability Company Supplement as dated
contemporaneously herewith, any other supplements and authorizations required by
Lender and all other instruments and documents (as the same may be amended from
time to time) executed by Borrower and delivered to Lender in connection with,
or as security for, the indebtedness evidenced by the Note, except any separate
environmental indemnity agreement.

      2. In addition, for value received, Guarantor hereby, unconditionally and
irrevocably, guarantees to Lender and its successors and assigns the full,
prompt and faithful payment of the full amount of the principal, interest and
any other sums due or to become due under the Loan Documents (the
"Indebtedness") upon and following the occurrence of a Triggering Event, it
being the intention hereof that, following the occurrence of a Triggering Event,
Guarantor shall remain liable until the Indebtedness shall be fully paid, (i)
notwithstanding any invalidity of, or defect or deficiency in any Loan Document,
(ii) notwithstanding the fact that Borrower may have no personal liability for
all or a portion of the Indebtedness and Lender's recourse against Borrower and
Borrower's assets may be limited, and (iii) notwithstanding any act, omission or
thing which might otherwise operate as a legal or equitable discharge of
Guarantor.

      Following the occurrence of a Triggering Event, Guarantor shall, within
five business days from the date a notice is given to Guarantor that an Event of
Default (as defined in the Lien Instrument) has occurred and is continuing, cure
such Event of Default. If any Event of Default shall not be cured by Guarantor
within said five business day period, Lender may, at its option, accelerate the
Indebtedness (if operation of a stay under the federal bankruptcy code or under
any other state or federal bankruptcy, insolvency or similar proceeding,
prohibits or delays acceleration of the Indebtedness as to Borrower, Guarantor
agrees that Guarantor's obligations hereunder shall not be postponed or reduced)
and, within five business days from the date a written demand from Lender is
given to Guarantor, Guarantor shall cure all Events of Default and pay all of
the Indebtedness, whether or not acceleration of the Indebtedness has occurred
as to Borrower.

      3. Any obligations not paid when due hereunder shall bear interest from
the date due until paid at the Default Rate (as defined in the Note). Guarantor
hereby waives absolutely and irrevocably, until the Indebtedness shall have been
paid in full, any right of subrogation whatsoever to Lender's claims against
Borrower and any right of indemnity, reimbursement or contribution from Borrower
with respect to any payment made or performance undertaken by Guarantor pursuant
hereto. If Borrower shall become a debtor under the federal bankruptcy code or
the subject of any other state or federal bankruptcy, insolvency or similar
proceeding, neither the operation of a stay nor the discharge of the
Indebtedness thereunder shall affect the liability of Guarantor hereunder.

      4. Without limiting or lessening the liability of Guarantor under this
Guarantee, Lender may, without notice to Guarantor:

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      (A)   Grant extensions of time or any other indulgences on the
            Indebtedness;

      (B)   Take, give up, modify, vary, exchange, renew or abstain from
            perfecting or taking advantage of any security for the Indebtedness;
            and

      (C)   Accept or make compositions or other arrangements with Borrower,
            realize on any security, and otherwise deal with Borrower, other
            parties and any security as Lender may deem expedient.

      5. This Guarantee shall be a continuing guarantee, shall not be revoked by
death, shall inure to the benefit of, and be enforceable by, any subsequent
holder of the Note and the Lien Instrument and shall be binding upon, and
enforceable against, Guarantor and Guarantor's heirs, legal representatives,
successors and assigns.

      6. All additional demands, presentments, notices of protest and dishonor,
and notices of every kind and nature, including those of any action or no action
on the part of Borrower, Lender or Guarantor, are expressly waived by Guarantor.
This is a guarantee of payment and not of collection. Guarantor hereby waives
the right to require Lender to proceed against Borrower or any other party, or
to proceed against or apply any security it may hold, waives the right to
require Lender to pursue any other remedy for the benefit of Guarantor and
agrees that Lender may proceed against Guarantor without taking any action
against any other party and without proceeding against or applying any security
it may hold. Lender may, at its election, foreclose upon any security held by it
in one or more judicial or non-judicial sales, whether or not every aspect of
such sale is commercially reasonable, without affecting or impairing the
liability of Guarantor, except to the extent the Indebtedness shall have been
paid. Guarantor waives any defense arising out of such an election,
notwithstanding that such election may operate to impair or extinguish any right
or any remedy of Guarantor against Borrower or any other security.

      7. Guarantor agrees to pay reasonable attorneys' fees and all other costs
and expenses which may be incurred in the enforcement of this Guarantee.

      8. Any notices, demands, requests and consents permitted or required
hereunder or under any other Loan Document shall be in writing, may be delivered
personally or sent by certified mail with postage prepaid or by reputable
courier service with charges prepaid. Any notice or demand sent to Guarantor by
certified mail or reputable courier service shall be addressed to Guarantor at
the address set forth opposite Guarantor's name below or such other address in
the United States of America as Guarantor shall designate in a notice to Lender
given in the manner described herein. Any notice sent to Lender by certified
mail or reputable courier service shall be addressed to The Northwestern Mutual
Life Insurance Company to the attention of the Real Estate Investment Department
at 720 East Wisconsin Avenue, Milwaukee, WI 53202 or at such other addresses as
Lender shall designate in a notice given in the manner described

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herein. Any notice given to Lender shall refer to the Loan No. set forth above.
Any notice or demand hereunder shall be deemed given when received. Any notice
or demand which is rejected, the acceptance of delivery of which is refused or
which is incapable of being delivered during normal business hours at the
address specified herein or such other address designated pursuant hereto shall
be deemed received as of the date of attempted delivery.

      9. The following terms shall be defined as set forth below:

      "Recourse Obligations" means the following:

      (A)   Rents and other income from the Property received by Borrower or
            those acting on behalf of Borrower after any Non-Monetary Default
            (as defined in the Lien Instrument) of which Borrower has received
            written notice and after any Monetary Default (as defined in the
            Lien Instrument) under the Loan Documents remaining uncured prior to
            the Conveyance Date (as hereinafter defined), which rents and other
            income have not been applied to the payment of principal and
            interest on the Note or to reasonable operating expenses of the
            Property;

      (B)   Amounts necessary to repair damage to the Property caused by
            intentional acts or omissions of Borrower or Borrower's agents, and
            to the extent funds would have been available from the Property,
            amounts necessary to repair damage to the Property caused by
            intentional omissions of Borrower or Borrower's agents;

      (C)   Insurance loss proceeds and Condemnation Proceeds (as defined in the
            Lien Instrument) released to Borrower but not applied in accordance
            with any agreement between Borrower and Lender as to their
            application;

      (D)   The amount of insurance loss proceeds which would have been
            available with respect to a casualty on the Property, but were not
            available due to the Event of Default by Borrower in carrying all
            insurance required by Lender;

      (E)   Damages suffered by Lender in connection with the Indebtedness as a
            result of fraud or material misrepresentation by Borrower or any
            other person or entity acting on behalf of Borrower;

      (F)   Amounts in excess of any rents or other revenues collected by Lender
            from operation of the Property from and after acceleration of the
            Note until the Conveyance Date, which amounts are necessary to pay
            real estate taxes, special assessments and insurance premiums (to
            the extent not previously deposited with Lender pursuant to the
            provisions of the Lien Instrument following the caption entitled
            "DEPOSITS BY MORTGAGOR"), amounts required

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            to fulfill Borrower's obligations as lessor under any leases of the
            Property, in each case, either paid by Lender and not reimbursed
            prior to, or remaining due or delinquent on, the Conveyance Date;

      (G)   All security deposits under leases of the Property or any portion of
            the Property collected by Borrower, any agent of Borrower or any
            predecessor of Borrower, and not refunded to the tenants thereunder
            in accordance with their respective leases, applied in accordance
            with such leases or law or delivered to Lender, and all advance
            rents collected by Borrower, any agent of Borrower or any
            predecessor of Borrower and not applied in accordance with the
            leases of the Property or delivered to Lender; and

      (H)   the entire Indebtedness in the event there is a violation of any
            provision of the Lien Instrument following the caption entitled
            "PROHIBITION ON TRANSFER".

      "Conveyance Date" means (i) the later of (a) the date on which title vests
in the purchaser at the foreclosure sale of the Property pursuant to the Lien
Instrument or (b) the date on which Borrower's statutory right of redemption
shall expire or be waived or (ii) the date of the conveyance of the Property to
Lender or its designee, assignee or successor in lieu of foreclosure.

      "Triggering Event" means any of the following:

      (A)   The filing by Borrower, AH Michigan Owner Limited Partnership, an
            Ohio limited partnership, a member of Borrower, ("AHMI") or AH
            Pennsylvania Owner Limited Partnership, an Ohio limited partnership,
            a member of Borrower, ("AHPA") of a voluntary petition for relief
            under the federal bankruptcy code, other than a voluntary petition
            filed against Borrower by The Northwestern Mutual Life Insurance
            Company, in its capacity as a member of Borrower, under the federal
            bankruptcy code;

      (B)   The filing of an involuntary petition against Borrower, AHMI, or
            AHPA other than by Lender or an affiliate thereof under the federal
            bankruptcy code; or

      (C)   Borrower, AHMI, or AHPA shall become the subject of any liquidation,
            receivership or other similar proceedings, other than as a result of
            the action of Lender or an affiliate thereof.

provided, however, that Guarantor shall not be liable for any outstanding
amounts due under the Indebtedness pursuant to clauses (B) and (C) above and the
remedies thereunder will not be available to Lender if:

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      (X)   Any of the proceedings referred to in clauses (B) and (C) above
            (collectively, the "Proceedings") is dismissed within ninety (90)
            days of being commenced;

      (Y)   Despite such Proceedings, Borrower, AHMI, or AHPA (as the case may
            be) shall, within ninety (90) days of the commencement of any such
            Proceedings, cure all defaults under the Loan Documents and
            thereafter perform Borrower's obligations under the Loan Documents
            (a) within five (5) business days after the due date of any payment
            required under the Loan Documents and (b) within 30 days after the
            date on which any other obligation under the Loan Documents is due;
            or

      (Z)   Despite such Proceedings, Borrower, AHMI, or AHPA (as the case may
            be) consents, stipulates or agrees to the lifting of any automatic
            stay and the removal of all other impediments to foreclosure of the
            Lien Instrument and otherwise cooperates with Lender and takes
            whatever steps are necessary to lift any automatic stay or to remove
            any other impediment to foreclosure and the enforcement of remedies
            available to Lender, thereby enabling Lender to foreclose the Lien
            Instrument (or enforce its other remedies under the Loan Documents
            not including clauses (B) and (C) above) within (a) ninety (90) days
            of the commencement of such Proceedings or (b) thirty (30) days
            after Borrower fails to perform an obligation under the Loan
            Documents within the applicable time period for performing such
            obligation as set forth in clause (Y) above.

      10. This Guarantee shall be governed by and construed in all respects in
accordance with the laws of the State of Michigan without regard to any conflict
of law principles. With respect to any action, lawsuit or other legal proceeding
concerning any dispute arising under or related to this Guarantee, Guarantor
hereby irrevocably consents to the jurisdiction of the courts located in the
State of Michigan and irrevocably waives any defense of improper venue, forum
nonconveniens or lack of personal jurisdiction in any such action, lawsuit or
other legal proceeding brought in any court located in the

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State of Michigan. Nothing contained herein shall affect the rights of Lender to
commence an action, lawsuit or other legal proceeding against Guarantor in any
other jurisdiction.

Executed as of the 30th day of September, 2003.

Mailing Addresses:

Brookdale Living Communities, Inc.       BROOKDALE LIVING
Attn: R. Stanley Young                   COMMUNITIES, INC., a
330 N. Wabash Avenue, Suite 1400         Delaware corporation
Chicago, IL 60611
                                         By: /s/ R. Stanley Young
                                             -----------------------------------
with a copy to:                              R. Stanley Young
                                             Its Executive Vice President, Chief
Brookdale Living Communities, Inc.           Financial Officer and Treasurer
Attn: Deborah Paskin
33 N. Wabash Avenue, Suite 1400
Chicago, IL 60611

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