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                                                                    EXHIBIT 31.0

                                  CERTIFICATION

I, Ronald E. Kimbrough, Executive Vice President and Chief Financial Officer
(Principal Financial and Accounting Officer and Acting Principal Executive
Officer) of Income Opportunity Realty Investors, Inc. ("IORI"), certify that:

1.   I have reviewed this annual report on Form 10-K of IORI;

2.   Based on my knowledge, this annual report does not contain any untrue
     statement of a material fact or omit to state a material fact necessary to
     make the statements made, in light of the circumstances under which such
     statements were made, not misleading with respect to the period covered by
     this annual report;

3.   Based on my knowledge, the financial statements, and other financial
     information included in this annual report, fairly present in all material
     respects the financial condition, results of operations and cash flows of
     the registrant as of, and for, the periods presented in this annual report;

4.   I am responsible for establishing and maintaining disclosure controls and
     procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) for
     the registrant and have:

     a.   designed such disclosure controls and procedures, or caused such
          disclosure controls and procedures to be designed under our
          supervision, to ensure that material information relating to the
          registrant, including its consolidated subsidiaries, is made known to
          us by others within those entities, particularly during the period in
          which this report is being prepared;

     b.   designed such internal control over financial reporting, or caused
          such internal control over financial reporting to be designed under
          our supervision, to provide reasonable assurance regarding the
          reliability of financial reporting and the preparation of financial
          statements for external purposes in accordance with generally accepted
          accounting principles;

     c.   evaluated the effectiveness of the registrant's disclosure controls
          and procedures and presented in this report our conclusions about the
          effectiveness of the disclosure controls and procedures, as of the end
          of the period covered by this report based on such evaluation; and

     d.   disclosed in this report any change in the registrant's internal
          control over financial reporting that occurred during the registrant's
          most recent fiscal quarter (the registrant's fourth fiscal quarter in
          the case of an annual report) that has


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          materially affected, or is reasonably likely to materially affect, the
          registrant's internal control over financial reporting.

5.   I have disclosed, based upon my most recent evaluation of internal control
     over financial reporting, to IORI's auditors and Audit Committee of the
     Board of Directors (or persons fulfilling the equivalent function):

     a.   all significant deficiencies and material weaknesses in the design or
          operation of internal control over financial reporting which are
          reasonably likely to adversely affect IORI's ability to record,
          process, summarize, and report financial information; and

     b.   any fraud, whether or not material, that involves management or other
          employees who have a significant role in IORI's internal controls over
          financial reporting.

Dated: March 31, 2004                         /s/ Ronald E. Kimbrough
                                              ----------------------------------
                                              Ronald E. Kimbrough
                                              Executive Vice President and Chief
                                              Financial Officer (Principal
                                              Financial and Accounting Officer
                                              and Acting Principal Executive
                                              Officer)


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