Document:

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                                                                    Exhibit 10.5

                           CONDITIONAL PROMISSORY NOTE

1. CONSIDERATION PAYABLE UNDER TERMS OF THIS PROMISSORY NOTE. Pursuant to
Section 2.2 of that certain Purchase Agreement (the "PURCHASE AGREEMENT") by and
between HomeSeekers.com, Incorporated, a Nevada corporation ("HOMESEEKERS") and
the sole members of Immediate Results through Intuitive Systems, LLC, a
California limited liability company ("IRIS"), who are Greg Robertson, Eddie
Ureno, Margaret G. Etheridge, and Dan Woolley (collectively, the "MEMBERS"),
HomeSeekers promises to convey shares of validly issued, fully paid and
nonassessable common stock, $.001 par value, of HomeSeekers ("HOMESEEKERS COMMON
STOCK") to the Members, in accordance with the following provisions:

         (a) FIRST MATURITY DATE. Upon the one hundred eightieth day following
the Closing Date, as such term is defined in the Purchase Agreement (the "FIRST
MATURITY DATE"), if the Value (as defined in Section 1(c) below) of the
HomeSeekers Common Stock issued to the Members pursuant to Section 2.1 of the
Purchase Agreement has not equaled or exceeded Eight Million Nine Hundred
Seventy-Five Thousand Dollars ($8,975,000) on any day during the preceding one
hundred eighty days, then HomeSeekers shall deliver to the Members, the
aggregate number of shares of HomeSeekers Common Stock equal to the lesser of
the following: (i) four hundred thousand (400,000) shares; or (ii) the
difference, as of the one hundred eightieth day following the Closing Date,
between Eight Million Nine Hundred Seventy-Five Thousand Dollars ($8,975,000)
and the Value of the HomeSeekers Shares issued pursuant to Section 2.1 of the
Purchase Agreement.

         (b) SECOND MATURITY DATE. Upon the first anniversary of the Closing
Date (the "SECOND MATURITY Date"), if the combined Value of any and all shares
of HomeSeekers Common Stock issued to the Members pursuant to Section 2.1 of the
Purchase Agreement and Section 1(a) of this Promissory Note has not equaled or
exceeded Eight Million Nine Hundred Seventy-Five Thousand Dollars ($8,975,000)
on any day during the preceding year, then HomeSeekers shall deliver to the
Members, the aggregate number of shares of HomeSeekers Common Stock equal to the
lesser of the following: (i) two million five hundred thousand (2,500,000)
shares; or (ii) the difference, on the first anniversary of the Closing Date,
between Eight Million Nine Hundred Seventy-Five Thousand Dollars ($8,975,000)
and the combined Value of any and all shares of HomeSeekers Common Stock issued
to the Members pursuant to Section 2.1 of the Purchase Agreement and Section
1(a) of this Promissory Note.

         (c) VALUATION OF HOMESEEKERS COMMON STOCK. For purposes of this Section
1, the "VALUE" of the HomeSeekers Common Stock for any chosen day shall equal:
(i) the applicable number of shares; multiplied by (ii) the average closing sale
price of a share of HomeSeekers stock on the Nasdaq SmallCap Market or other
applicable exchange for the trading days within the thirty (30) calendar days
preceding the applicable date.

         (d) WRITTEN INSTRUCTIONS. Any HomeSeekers Common Stock that is required
to be issued and delivered pursuant to this Promissory Note shall be divided
among the Members in accordance with written instructions signed by all of the
Members and delivered to HomeSeekers.

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2. HOLD BACK AND SET OFF FOR INDEMNIFICATION OBLIGATIONS UNDER PURCHASE
AGREEMENT. Any and all HomSeekers Common Stock issuable and deliverable pursuant
to this Promissory Note is subject to set off and hold back rights to secure the
indemnification obligations of the Members under Article X of the Purchase
Agreement, as more fully described in Article X of the Purchase Agreement.

3 GOVERNING LAW, JURISDICTION AND WAIVER OF VENUE. This Promissory Note shall be
governed by and construed in accordance with the laws of the State of Nevada
regardless of the fact that any of the parties hereto may be or may become a
resident of a different country, state, or jurisdiction. Any suit, action or
proceeding arising out of, or with respect to, this Promissory Note shall be
filed in a court of competent jurisdiction within the County of Washoe, State of
Nevada or in the U.S. District Court for the District of Nevada, Northern
Division. The parties hereby consent to the personal jurisdiction of such courts
within the County of Washoe, State of Nevada and the U.S. District Court for the
District of Nevada, Northern Division. The parties hereby waive any objections
to venue in such courts within Washoe County, State of Nevada and the U.S.
District Court for the District of Nevada, Northern Division.

4. WAIVER. This Promissory Note may not be modified, amended, supplemented,
canceled, or discharged, except by written instrument executed by HomeSeekers
and each of the Members. The failure of the Members to enforce any of the
provisions of this Promissory Note shall not impair the rights of the Members to
require observance, performance, or satisfaction, either of that term or
condition as it applies on a subsequent occasion or of any other term or
condition of this Promissory Note.

5. BINDING. This Promissory Note shall bind HomeSeekers and HomeSeekers'
successors and assigns and the benefits hereof shall inure to the Members and
each of the Members' heirs, representatives, successors and assigns; PROVIDED,
HOWEVER, that HomeSeekers shall not assign its obligations under this Promissory
Note, by operation of law or otherwise, without each Member's prior written
consent.

6. SEVERABILITY. If any term or provision of this Note or the application
thereof to any person or circumstances shall, to any extent, be invalid or
unenforceable, the remainder of this Promissory Note, or the application of such
term or provision to persons or circumstances other than those as to which it is
held invalid or unenforceable, shall not be affected thereby. Each term and
provision of this Promissory Note shall be valid and enforceable to the fullest
extent permitted by law.

7. ATTORNEYS' FEES AND COSTS, ETC. In any action or proceeding arising out of or
related to this Promissory Note, or the transactions contemplated hereby, the
prevailing party therein shall be entitled to recover from the other party the
reasonable attorneys' and paralegals', accountants' and experts' fees, court
costs, filing fees, publication costs and other expenses incurred by the
prevailing party in connection therewith.

8. FURTHER ASSURANCES. Each of HomeSeekers and the Members shall, at the request
of the other, furnish, execute, and deliver such documents, instruments,
certificates, notices or other

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further assurances as the requesting party shall reasonably request as necessary
or desirable to effect complete consummation of this Agreement and the
transactions contemplated hereby.

Dated July 21, 2000.

                                   HOMESEEKERS.COM, INCORPORATED,
                                   a Nevada corporation

                                   By: /s/ Greg Costley
                                       ---------------------------------------
                                   Name: Greg Costley
                                        --------------------------------------
                                   Title: Chairman and Chief Executive Officer
                                          ------------------------------------<PAGE>

CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED BY BRACKETS,
HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND EXCHANGE
COMMISSION PURSUANT TO RULE 24b-2 OF THE SECURITIES EXCHANGE ACT OF 1934, AS
AMENDED.

                                                                 EXHIBIT 10.31

      SECOND AMENDMENT TO THE AMENDED AND RESTATED RESEARCH, DEVELOPMENT
      AND MARKETING COLLABORATION AGREEMENT BETWEEN ONYX PHARMACEUTICALS,
      INC., A DELAWARE CORPORATION ("ONYX"), AND WARNER-LAMBERT COMPANY,
                      A DELAWARE CORPORATION ("WARNER")

         THIS SECOND AMENDMENT ("Second Amendment") between Onyx and Warner,
which Agreement was amended and restated July 1997, the AMENDED AND RESTATED
RESEARCH, DEVELOPMENT AND MARKETING COLLABORATION AGREEMENT as amended by that
certain Amendment dated December 15, 1997 (as amended, the "Agreement"), dated
as of May 2, 1995, is entered into and made effective March 1, 2000. Onyx and
Warner may be referred to herein individually as "Party," or collectively, as
the "Parties."

                                   RECITALS

         WHEREAS, Onyx and Warner desire to amend the Agreement to modify the
scope, personnel, resources, term, and research funding.

         NOW, THEREFORE, in consideration of the covenants contained in this
Second Amendment, the Parties hereby agree as follows:

          1.      Section 2.1, Undertaking and Scope, is amended to delete only
                  the fourth (4th) sentence, and replace it with the following:

                  Onyx agrees to use its best efforts at its cost [ * ] to
                  supply protein required to run screening assays relating to
                  biochemical targets, which targets were identified and
                  transferred to Warner prior to the Effective Date of this
                  Amendment.

          2.      Section 2.2, Personnel and Resources, is amended to delete
                  only the second (2nd) sentence, and replace it with the
                  following:

                  From the effective date of the Agreement until March 1, 2000,
                  Warner and Onyx will each maintain at their cost an average of
                  [ * ] full-time equivalents ("FTEs") devoted to cooperative
                  work under the Research Plan. Starting March 1, 2000 until the
                  end of the Term of the Research Collaboration, the number of
                  FTEs that Onyx shall devote to the cooperative work shall be
                  reduced to [ * ]. The number of FTEs may, however, be
                  increased up to [ * ] by the Research Management Committee
                  provided there is a concomitant reduction in the number of
                  FTEs that are working on the Research, Development and
                  Marketing Collaboration

                                       1.
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                  Agreement pertaining to Inflammation ("Inflammation
                  Agreement"), having an effective date of July 31, 1997.

          3.      Section 2.3, Term of the Research Collaboration, is hereby
                  deleted in its entirety and replaced by the following:

                  2.3  Research Term. Work under the Research Plan will commence
                  as of May 2, 1995 and, unless terminated earlier by either
                  party pursuant to the terms of this Agreement or extended by
                  mutual agreement of the Parties, will terminate on August 31,
                  2001.

          4.      Section 9.1, Research Funding, is amended to delete the
                  months May 2, 2000 through February 2, 2001 and substitute
                  therefor the following:

                  June 1, 2000                       [ * ]
                  Sept. 1, 2000                      [ * ]
                  Dec. 1, 2000                       [ * ]
                  Mar. 1, 2001                       [ * ]
                  June 1, 2001                       [ * ]

          5.      Except as otherwise specifically set forth herein, all of the
                  terms and conditions of the Agreement shall remain in full
                  force and effect.

         IN WITNESS WHEREOF, the Parties have caused this Amendment to be
executed by their duly authorized officers as of the date first written above.

ONYX PHARMACEUTICALS, INC.                   WARNER-LAMBERT COMPANY

By:    /s/ Hollings C. Renton                By:    /s/ Peter B. Corr
       -----------------------------                --------------------------

Name:   Hollings C. Renton                   Name:   Peter B. Corr, Ph.D.
       -----------------------------                --------------------------

Title:  President & CEO                      Title:  Corporate Vice-President,
       -----------------------------                --------------------------
                                                      Warner-Lambert Company
                                                      President, Parke-Davis
                                                      Pharmaceutical Research
                                                      & Development

[ * ] = CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED BY
BRACKETS, HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND EXCHANGE
COMMISSION PURSUANT TO RULE 24b-2 OF THE SECURITIES EXCHANGE ACT OF 1934, AS
AMENDED.

                                       2.

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