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Exhibit 10.4

        SIXTH AMENDMENT, dated as of September 30, 2003 (this "Amendment"), to
the INTERIM CREDIT AGREEMENT, dated as of March 11, 2002 (as amended by the
First Amendment and Waiver, dated as of June 12, 2002, the Second Amendment,
dated as of August 2, 2002, the Third Amendment, dated as of February 14, 2003,
the Fourth Amendment, dated as of May 9, 2003, and the Fifth Amendment, dated as
of May 30, 2003, and as further amended, restated, extended, supplemented or
otherwise modified in writing from time to time, the "Credit Agreement"), among
AIMCO PROPERTIES, L.P., a Delaware limited partnership ("AIMCO"), NHP MANAGEMENT
COMPANY, a District of Columbia corporation ("NHP Management"), and APARTMENT
INVESTMENT AND MANAGEMENT COMPANY, a Maryland corporation (the "REIT") (AIMCO,
NHP Management and the REIT are collectively referred to herein as "Borrowers"),
LEHMAN COMMERCIAL PAPER INC., as Administrative Agent (in such capacity, the
"Administrative Agent"), as Syndication Agent and as a Lender, each lender from
time to time party thereto and LEHMAN BROTHERS INC., as Sole Lead Arranger and
Bookrunner.

W I T N E S S E T H:

        WHEREAS, pursuant to the Credit Agreement, the Lenders have agreed to
make, and have made, certain Loans and other extensions of credit to the
Borrowers;

        WHEREAS, the Borrower has requested that the Lenders agree to make
certain amendments to the Credit Agreement;

        WHEREAS, the Lenders have agreed to make such amendments solely upon the
terms and conditions provided for in this Amendment;

        NOW, THEREFORE, the parties hereto agree as follows:

        1.     Defined Terms. Unless otherwise noted herein, terms defined in
the Credit Agreement and used herein shall have the meanings given to them in
the Credit Agreement.

        2.     Amendments to Section 1.01 of the Credit Agreement (Defined
Terms).

        (a)   Section 1.01 of the Credit Agreement is hereby amended by deleting
the following definitions in their entirety:

        (i)    "Adjusted Fixed Charges" and

        (ii)   "Adjusted Fixed Charges Coverage Ratio".

        (b)   Section 1.01 of the Credit Agreement is hereby further amended by
inserting the following new definitions in the appropriate alphabetical order:

        "Leverage Premium" means, upon the Borrowers' election of a Temporary
Leverage Increase for more than two consecutive quarters, an additional 25 basis
points

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per annum increase in the Applicable Margin. The Leverage Premium shall be in
effect from the date the Compliance Certificate in which the Borrowers have
elected a Temporary Leverage Increase for more than two consecutive quarters is
received by Administrative Agent to but excluding the date the next Compliance
Certificate in which the Borrowers do not elect a Temporary Leverage Increase is
received by Administrative Agent.

        "Mirror Notes" means the indemnity obligations of The Casden Company, a
California corporation ("The Casden Company"), to NAPICO, which may be evidenced
by certain non-recourse promissory notes issued by The Casden Company or one of
its Affiliates to NAPICO or one of its Affiliates, which will have the same
interest rate and maturity schedule as the NAPICO Notes.

        "REAL Litigation Settlement Agreement" means that certain Settlement
Agreement, dated as of August 12, 2003, by and among the REIT, AIMCO, National
Partnership Investment Corp., a California corporation ("NAPICO"), Cerberus
Partners, L.P., a Delaware limited partnership, XYZ Holdings, LLC, a Delaware
limited liability company, Alan I. Casden, an individual, The Casden Company, a
California corporation and Casden Investment Corp., a California corporation
with respect to the settlement of In re Real Estate Associates Limited
Partnership Litigation, CV 98-7035 DDP, United States District Court, Central
District of California (the "REAL Litigation").

        "REAL Litigation Settlement Obligations" means, collectively, (i) Loans
in the aggregate principal amount of $25,000,000 which were used by the REIT or
one of its Affiliates to make a cash deposit in escrow for the benefit of the
plaintiffs of the REAL Litigation (the "Cash Deposit"), and (ii) certain
promissory notes made by NAPICO in the aggregate amount of $35,000,000 in favor
of the plaintiffs of the REAL Litigation (the "NAPICO Notes") and that certain
Guaranty made by AIMCO in favor of the plaintiffs of the REAL Litigation with
respect to the payment and performance of the NAPICO Notes (the "REAL Litigation
Guaranty").

        "REAL Litigation Settlement Pledged Stock" means, collectively,
(i) 531,915 shares of common Stock of the REIT placed in escrow by The Casden
Company for release to the REIT in connection with the Cash Deposit (the "Cash
Deposit Stock"), as such number of shares may be reduced from time to time
pursuant to the REAL Litigation Settlement Agreement, and (ii) 744,681 shares of
common Stock of the REIT (plus up to 60,000 additional shares for accrued
interest) pledged by The Casden Company or one of its Affiliates to NAPICO to
secure the payment of the Mirror Notes (the "Mirror Notes Stock") as such number
of shares may be reduced from time to time pursuant to the REAL Litigation
Settlement Agreement.

        "Temporary Leverage Increase" means, upon the Borrowers' election by
indicating their election in writing on the quarterly Compliance Certificate
delivered to Administrative Agent pursuant to Section 6.02(b), an increase in
the ratios set forth in either Section 7.14(e) or (f). A Temporary Leverage
Increase shall be in effect for the fiscal quarter elected by the Borrowers on
the Compliance Certificate.

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        (c)   Section 1.01 of the Credit Agreement is hereby further amended by
deleting the definition of "Applicable Margin" in its entirety and substituting
in lieu thereof the following:

        "Applicable Margin" means, with respect to Base Rate Loans, 1.85% per
annum, plus the additional amount of the Leverage Premium, if applicable, and
with respect to Offshore Rate Loans, 2.85% per annum, plus the additional amount
of the Leverage Premium, if applicable, provided that in each case, if at any
time (i) any credit rating of either AIMCO's or the REIT's obligations under
their respective senior unsecured debt or either AIMCO's or the REIT's corporate
credit rating is downgraded from its current level on the Closing Date as set
forth on Schedule 1.01F by either Moody's or S&P or (ii) the credit rating of
this Agreement, if rated, is downgraded from its initial rating by either
Moody's or S&P, the Applicable Margin for Base Rate Loans shall be 2.10% per
annum, plus the additional amount of the Leverage Premium, if applicable, and
the Applicable Margin for Offshore Rate Loans shall be 3.10% per annum, plus the
additional amount of the Leverage Premium, if applicable, for the period
beginning on the effective date of such downgrade until the date such rating is
at least the level in effect on the Closing Date or such initial rating, as the
case may be.

        (d)   Section 1.01 of the Credit Agreement is hereby further amended by
deleting the "." at the end of the last sentence of the definition of "Funds
from Operations" and replacing it with the following:

        ; provided, however, the following shall be excluded when calculating
"Funds From Operations": (i) non-cash adjustments for preferred Stock issuance
costs, (ii) non-cash adjustments for loan amortization costs, and (iii) interest
expense charges (or benefits) for minority interest marked-to-market adjustments
arising under Statement of Financial Accounting Standards No. 150 of the
Financial Accounting Standards Board ("FAS 150") as interpreted under GAAP.

        (e)   Section 1.01 of the Credit Agreement is hereby further amended by
deleting the word "9.00" from clauses (c) and (d) of the definition of "Gross
Asset Value", and replacing it with the word "8.75".

        (f)    Section 1.01 of the Credit Agreement is hereby further amended by
adding the following words to the definition of "Indebtedness" immediately after
the last sentence thereof:

        Notwithstanding the foregoing, "Indebtedness" shall only include the net
obligations of the REIT, AIMCO and NAPICO under the REAL Litigation Settlement
Agreement, which shall be calculated quarterly based on the sum of (x) the
difference of (A) $25,000,000 less (B) an amount equal to the product of (1) the
then remaining number of shares of Cash Deposit Stock held by the REIT or an
Affiliate of the REIT in escrow times (2) the average closing share price of
such Cash Deposit Stock on the NYSE over the 21 trading day period immediately
prior to each quarter-end, and (y) the

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difference of (A) (without duplication) the outstanding NAPICO Notes and the
REAL Litigation Guaranty less (B) an amount equal to the product of (1) the then
remaining number of shares of Mirror Notes Stock held by NAPICO or an Affiliate
of NAPICO as pledgee times (2) the average closing share price of such Mirror
Notes Stock on the NYSE over the 21 trading day period immediately prior to each
quarter-end. In all events, the net obligations of the REIT, AIMCO and NAPICO
under the REAL Litigation Settlement Agreement shall not be less than zero.

        (g)   Section 1.01 of the Credit Agreement is hereby further amended by
deleting the words "Notwithstanding the foregoing, amortization of loan costs
and interest accrued under any Intra-Company Debt shall not be included within
"Interest Expense" for any purposes hereof." from the definition of "Interest
Expense", and replacing them with the following:

        Notwithstanding the foregoing, "Interest Expense" shall not include
(i) amortization of loan costs and interest accrued under any Intra-Company Debt
or (ii) interest expense charges (or benefits) from minority interest
marked-to-market adjustments arising under FAS 150 as interpreted under GAAP.

        3.     Amendment to Section 1.03 of the Credit Agreement. Section 1.03
of the Credit Agreement is hereby amended by deleting it in its entirety and
substituting in lieu thereof the following:

        (a)   All accounting terms not specifically or completely defined in
this Agreement shall be construed in conformity with, and all financial data
(including financial ratios and other financial calculations but excluding
financial statements) required to be submitted by this Agreement shall be
prepared in conformity with, GAAP as in effect on September 30, 2003, except as
otherwise specifically prescribed herein.

        (b)   If at any time any change in GAAP would affect the computation of
any financial ratio or requirement set forth in this Agreement, and either
Borrowers, Administrative Agent or Requisite Lenders shall so request,
Administrative Agent, Lenders and Borrowers shall negotiate in good faith to
amend such ratio or requirement to preserve the original intent thereof in light
of such change in GAAP (subject to the approval of Requisite Lenders,
Administrative Agent and Borrowers); provided, that, until so amended, such
ratio or requirement shall continue to be computed in accordance with GAAP prior
to such change therein.

        4.     Amendment to Section 6.02 of the Credit Agreement. Section 6.02
of the Credit Agreement is hereby amended by, immediately after the words "(1) a
duly completed Compliance Certificate signed by a Responsible Officer of the
Borrowers, with such supporting information as may be requested by
Administrative Agent," adding the following:

including a statement as to whether any change in GAAP or in the application
thereof has occurred since September 30, 2003, and, if any change has occurred,
specifying the effect of such change on the financial statements accompanying
such Compliance Certificate

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and setting forth a certified reconciliation between calculations of the
financial ratios or requirements made before and after giving effect to such
change in GAAP,

        5.     Amendment to Section 7.05 of the Credit Agreement. Section 7.05
is hereby amended by deleting the word "and" at the end of clause (m) thereof,
deleting the period from the end of clause (n) thereof and replacing it with ";
and" and adding a new clause (o) which will read as follows:

        (o)   Investments in the Mirror Notes and the REAL Litigation Settlement
Pledged Stock securing the Mirror Notes required pursuant to the REAL Litigation
Settlement Agreement.

        6.     Amendment to Section 7.07 of the Credit Agreement.

        (a)   Section 7.07(a)(B) is hereby amended by deleting the words "(1)
(x) 88% of Funds From Operations for each four consecutive fiscal quarter period
ending on June 30, 2003, September 30, 2003, December 31, 2003 and March 31,
2004, (y) 85% of Funds From Operations for each four consecutive fiscal quarter
period ending on June 30, 2004 and September 30, 2004, or (z) 80% of Funds From
Operations for each four consecutive fiscal quarter period ending on the last
day of each fiscal quarter thereafter, or" and replacing them with the
following:

        (1)   90% of Funds From Operations for each four consecutive fiscal
quarter period ending on the last day of each fiscal quarter, or

        (b)   Section 7.07(a)(B) is hereby further amended by deleting the words
"; and (C)" and replacing them with the words "; (C)".

        (c)   Section 7.07(a) is hereby further amended by adding a new
clause (D) immediately preceding the words "provided, however" which will read
as follows:

        and (D) (1) the exercise by the Borrowers of their right as a secured
party to take possession of the Mirror Notes Stock after a default under the
Mirror Notes Stock pledge agreement and in accordance with the REAL Litigation
Settlement Agreement, and (2) the release to the Borrowers of the Cash Deposit
Stock currently held in escrow for the benefit of the Borrowers in accordance
with the REAL Litigation Settlement Agreement;

        7.     Amendments to Section 7.14 of the Credit Agreement.

        (a)   Section 7.14(a) is hereby amended by deleting the word "1.50" and
replacing it with the word "1.40".

        (b)   Section 7.14(b) is hereby amended by deleting it in its entirety
and substituting in lieu thereof the words "Intentionally Omitted."

        (c)   Section 7.14(c) is hereby amended by deleting the word "2.25" and
replacing it with the word "2.00".

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        (d)   Section 7.14(e) is hereby amended by inserting the words "at any
time during a Temporary Leverage Increase, the ratio shall not exceed
0.575:1.00; and provided, further," immediately following the words "provided,
however".

        (e)   Section 7.14(f) is hereby amended by deleting the words "Permit
the ratio of Total Obligations to Gross Asset Value to exceed 0.68:1.00 at any
time up to and including September 30, 2002, nor permit the ratio of Total
Obligations to Gross Asset Value to exceed 0.65:1.00 at October 1, 2002 or any
time thereafter; provided, however," and replacing it with the following:

        Permit the ratio of Total Obligations to Gross Asset Value to exceed
0.65:1.00 at any time; and provided, however, at any time during a Temporary
Leverage Increase, the ratio shall not exceed 0.675:1.00; provided, further,

        (f)    Section 7.14(g) is hereby amended by deleting the word "1.60" and
replacing it with the word "1.50".

        8.     Amendment to Exhibits to the Credit Agreement. Exhibit B—Form of
Compliance Certificate shall be deleted in its entirety and replaced with
Exhibit B—Form of Compliance Certificate attached hereto as Annex I.

        9.     Conditions to Effectiveness. This Amendment shall become
effective on the date on which all of the following conditions precedent have
been satisfied or waived (the "Effective Date"):

        (a)   The Administrative Agent shall have received five counterparts
hereof duly executed and delivered by each Borrower.

        (b)   The Administrative Agent shall have received executed Lender
Consent Letters, substantially in the form of Exhibit A hereto ("Lender Consent
Letters"), from the Supermajority Lenders.

        (c)   Guarantors and Pledgors shall have executed this Amendment with
respect to Section 14.

        (d)   The Administrative Agent shall have received for the account of
each Lender that executes and delivers to the Administrative Agent a Lender
Consent Letter at or prior to 5:00 P.M., New York City time, on October 30,
2003, a consent fee equal to 0.10% of the aggregate unpaid principal amount of
such Lender's Loans on such date.

        (e)   If required by Administrative Agent, Lenders and their respective
counsel shall have received originally executed copies of one or more favorable
written opinions of counsel for Borrowers, Guarantors and Pledgors in form and
substance satisfactory to Administrative Agent and its counsel, dated as of
Effective Date, with respect to the validity, binding effect and enforceability
of this Amendment, and due authorization, execution and delivery thereof, and as
to such other matters as Administrative Agent acting on behalf of Lenders may
request.

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        (f)    Borrowers shall have paid the fees, costs and expenses of
Administrative Agent's counsel in connection with this Amendment.

        (g)   Administrative Agent shall have received evidence satisfactory to
it and its counsel that the Revolver Administrative Agent and the Lenders (as
defined in the Revolving Credit Agreement) (i) have modified, or concurrently
with the Effective Date will modify, the Loans (as defined in the Revolving
Credit Agreement) and the Revolving Credit Agreement in a manner satisfactory to
the Administrative Agent and the Lenders and Administrative Agent shall have
been provided with true, correct and complete copies of the documents effecting
such modifications to the Loans (as defined in the Revolving Credit Agreement)
and the Revolving Credit Agreement and (ii) have consented to or waived their
right to consent to the Borrowers', Guarantors' and Pledgors' execution and
delivery of this Amendment.

        (h)   Administrative Agent shall have received evidence satisfactory to
it and its counsel that the Term Agent (as defined herein) and the Lenders (as
defined in the Term Loan Credit Agreement) (i) have modified, or concurrently
with the Effective Date will modify, the Loan (as defined in the Term Loan
Credit Agreement) and the Term Loan Credit Agreement in a manner satisfactory to
Administrative Agent and the Lenders and Administrative Agent shall have been
provided with true, correct and complete copies of the documents effecting such
modifications to the Loan (as defined in the Term Loan Credit Agreement) and
Term Loan Credit Agreement and (ii) have consented to or waived their right to
consent to the Borrowers', Guarantors' and Pledgors' execution and delivery of
this Amendment.

        (i)    Lenders and their respective counsel shall have received executed
resolutions or other action, incumbency certificates and/or other certificates
of Responsible Officers of each Borrower Party, Guarantors and Pledgors as
Administrative Agent may require to establish the identities of and verify the
authority and capacity of each Responsible Officer thereof authorized to act as
a Responsible Officer thereof.

        10.   Representations and Warranties. Each of the Borrowers hereby
represents and warrants to Administrative Agent and each Lender that (before and
after giving effect to this Amendment):

        (a)   Each Borrower, Guarantor and Pledgor has all requisite corporate
or other entity power and authority to enter into this Amendment and to carry
out the transactions contemplated by, and perform its obligations under, the
Credit Agreement as amended by this Amendment (the "Amended Agreement") and each
Loan Document to which it is a party.

        (b)   The execution and delivery of this Amendment and the performance
of the Amended Agreement and of each other Loan Document have been duly
authorized by all necessary corporate or other entity action on the part of each
Borrower Party that is a party thereto. Except as set forth on Schedule 10(b)
hereto, the organizational documents of the Borrowers, Pledgors and Guarantors
have not been modified in any material respect since May 30, 2003.

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        (c)   The execution, delivery, and performance by each Borrower, Pledgor
and Guarantor of this Amendment and compliance with the provisions thereof do
not and will not (i) violate or conflict with, or result in a breach of, or
require any consent under (A) any Organization Documents of such Borrower Party
or any of its Subsidiaries, (B) any applicable material Laws, rules, or
regulations or any order, writ, injunction, or decree of any Governmental
Authority or arbitrator, or (C) any Contractual Obligation of such Borrower
Party or any of its Subsidiaries or by which any of them or any of their
property is bound or subject, or (ii) constitute a default under any such
agreement or instrument, or (iii) result in, or require, the creation or
imposition of any Lien on any of the Properties of such Borrower Party or any of
its Subsidiaries, except, in each case under this clause (c), as provided in
Section 5.03 of the Credit Agreement.

        (d)   The execution, delivery and performance by each Borrower Party,
Pledgor and Guarantor of this Amendment to which it is a party do not and will
not require any authorization of a Governmental Authority (other than any
authorizations of a Governmental Authority obtained on or before the Effective
Date and disclosed in writing to the Lenders).

        (e)   This Amendment has been duly executed and delivered by each
Borrower Party party thereto and this Amendment is the legally valid and binding
obligations of such Borrower Parties party thereto, enforceable against such
Borrower Parties in accordance with their respective terms, except as may be
limited by bankruptcy, insolvency, reorganization, moratorium or similar laws
relating to or limiting creditors' rights generally or by equitable principles
relating to enforceability.

        (f)    The representations and warranties in Section V of the Credit
Agreement are true, correct and complete in all material respects on and as of
the Effective Date to the same extent as though made on and as of that date (or,
to the extent such representations and warranties specifically relate to an
earlier date, were true, correct and complete in all material respects on and as
of such earlier date).

        (g)   Borrowers and the other Borrower Parties have performed in all
material respects all agreements and satisfied all conditions which this
Amendment, the Credit Agreement and the other Loan Documents provide shall be
performed or satisfied by Borrowers or the other Borrower Parties on or before
the Effective Date.

        (h)   After giving effect to this Amendment, no Default or Event of
Default has occurred and is continuing, or will result from the consummation of
the transactions contemplated by this Amendment.

        11.   Payment of Expenses. The Borrowers jointly and severally agree to
pay or reimburse the Administrative Agent for all of its reasonable
out-of-pocket costs and expenses incurred in connection with this Amendment, any
other documents prepared in connection herewith and the transactions
contemplated hereby, including, without limitation, the reasonable fees and
disbursements of counsel to the Administrative Agent.

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        12.   No Other Amendments; Confirmation. Except as expressly provided
hereby, all of the terms and provisions of the Credit Agreement and the other
Loan Documents are and shall remain in full force and effect. The amendments
contained herein shall not be construed as an amendment of any other provision
of the Credit Agreement or the other Loan Documents or for any purpose except as
expressly set forth herein or a consent to any further or future action on the
part of the Borrowers that would require the waiver or consent of the
Administrative Agent or the Lenders.

        13.   GOVERNING LAW; Miscellaneous. (a) THIS AMENDMENT AND THE RIGHTS
AND OBLIGATIONS OF THE PARTIES HERETO SHALL BE GOVERNED BY AND CONSTRUED IN
ACCORDANCE WITH THE LAW OF THE STATE OF NEW YORK.

        (b)   On and after the Effective Date, each reference in the Credit
Agreement to "this Agreement", "hereunder", "hereof", "herein", or words of like
import referring to the Credit Agreement, and each reference in the other Loan
Documents to the "Credit Agreement", "thereunder", "thereof", or words of like
import referring to the Credit Agreement shall mean and be a reference to the
Amended Agreement.

        (c)   This Amendment may be executed by one or more of the parties to
this Agreement on any number of separate counterparts, and all of said
counterparts taken together shall be deemed to constitute one and the same
instrument. A set of the copies of this Amendment, each Amended Document and the
Lender Consent Letters signed by all the parties shall be lodged with the
Borrowers and the Administrative Agent. This Amendment may be delivered by
facsimile transmission of the relevant signature pages hereof.

        (d)   This Amendment embodies the entire agreement and understanding
among the parties with respect to the amendment to the Credit Agreement, and
supersedes all prior agreements and understandings, oral or written, relating
thereto.

        (e)   The execution and delivery of the Lender Consent Letter by any
Lender shall be binding upon each of its successors and assigns (including
assignees of its Loans in whole or in part prior to effectiveness hereof).

        14.   Acknowledgement and Consent.

        (a)   Guarantors are party to that certain Amended and Restated Payment
Guaranty, dated as of May 30, 2003, to the extent amended hereby, pursuant to
which Guarantors have guarantied the Obligations. Pledgors are party to that
certain Borrowers Pledge Agreement, dated as of May 30, 2003, to the extent
amended hereby, pursuant to which Pledgors have pledged the Pledged Collateral
as security for the Secured Obligations (as defined in the Borrowers Pledge
Agreement).

        (b)   Each Guarantor and each Pledgor hereby acknowledges that it has
reviewed the terms and provisions of the Credit Agreement and this Amendment and
consents to the amendment of the Credit Agreement effected pursuant to this
Amendment. Each Guarantor hereby confirms that each Guaranty to which it is a
party or otherwise bound, and each Pledgor hereby confirms that the Pledge
Agreement to

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which it is a party or otherwise bound, will continue to guaranty or secure, as
the case may be, to the fullest extent possible the payment and performance of
all of the "Indebtedness" (as defined in the applicable Guaranty) or the
"Secured Obligations" (as defined in the Borrowers Pledge Agreement), as the
case may be, including without limitation the payment and performance of all
such "Indebtedness" or "Secured Obligations", as the case may be, with respect
to the Obligations of Borrowers now or hereafter existing under or in respect of
the Credit Agreement (as amended hereby) and the Notes defined therein.

        (c)   Each Guarantor acknowledges and agrees that any Guaranty to which
it is a party or otherwise bound, and each Pledgor acknowledges and agrees that
the Pledge Agreement to which it is a party or otherwise bound, shall continue
in full force and effect and that all of its obligations thereunder shall be
valid and enforceable and shall not be impaired or limited by the execution or
effectiveness of this Amendment. Each Guarantor and each Pledgor represents and
warrants that all representations and warranties contained in the Credit
Agreement and the Guaranty and/or the Pledge Agreement, as the case may be, to
which it is a party or otherwise bound are true, correct and complete in all
material respects on and as of the Effective Date to the same extent as though
made on and as of that date, except to the extent such representations and
warranties specifically relate to an earlier date, in which case they were true,
correct and complete in all material respects on and as of such earlier date.

        (d)   Each Guarantor and each Pledgor acknowledges and agrees that
(i) notwithstanding the conditions to effectiveness set forth in this Amendment,
such Guarantor or such Pledgor, as the case may be, is not required by the terms
of the Credit Agreement or any other Loan Document to consent to the amendments
to the Credit Agreement effected pursuant to this Amendment and (ii) nothing in
the Credit Agreement, this Amendment or any other Loan Document shall be deemed
to require the consent of such Guarantor or such Pledgor to any future
amendments to the Credit Agreement.

        (e)   Each Lender hereby (i) acknowledges that it has received and
reviewed the terms and provisions of that certain Third Amendment to Fifth
Amended and Restated Credit Agreement, dated as of September 30, 2003 (the
"Revolver Amendment") among the REIT, AIMCO, NHP Management, and AIMCO/Bethesda
Holdings, Inc., a Delaware corporation (collectively, the "Revolver Borrowers"),
Bank of America, N.A., as administrative agent, each lender from time to time
party thereto, and (ii) consents to the modifications and amendments as set
forth in the Revolver Amendment to the Revolving Credit Agreement and the
Revolving Loan Documents.

        (f)    Each Lender hereby (i) acknowledges that it has received and
reviewed the terms and provisions of that certain First Amendment to Term Loan
Credit Agreement, dated as of September 30, 2003 (the "Term Amendment") among
the REIT, AIMCO, NHP Management and AIMCO/Bethesda (collectively, the "Term
Borrowers"), Bank of America, N.A., as administrative agent (in such capacity,
the "Term Agent"), each lender from time to time party thereto, and
(ii) consents to the modifications and

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amendments as set forth in the Term Amendment to the Term Loan Credit Agreement
and the Term Loan Documents.

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Exhibit 10.4