EXHIBIT 31
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                    CERTIFICATION PURSUANT TO RULE 13a-14(a),
                       AS ADOPTED PURSUANT TO SECTION 302
                        OF THE SARBANES-OXLEY ACT OF 2002

I, Joseph M. Jayson, Individual General Partner and Principal Financial Officer
of Realmark Property Investors Limited Partnership - III, hereby certify that:

     1.  I have reviewed this quarterly report on Form 10-Q for the period ended
         March 31, 2007 of Realmark Property Investors Limited Partnership -
         III;

     2.  Based on my knowledge, this quarterly 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 quarterly report;

     3.  Based on my knowledge, the financial statements, and other financial
         information included in this quarterly report, fairly present in all
         material respects the financial condition, results of operations and
         cash flows of the Partnership as of, and for, the periods presented in
         this quarterly 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)) and internal control over financial reporting (as defined in
         Exchange Act Rules 13a-15(f) and 15d-15(f)) for the Partnership and I
         have:

         a.     Designed such disclosure controls and procedures, or caused such
                disclosure controls and procedures to be designed under my
                supervision, to ensure the material information relating to the
                Partnership, including its consolidated subsidiary, is made
                known to me by others within the Partnership, particularly
                during the period in which this quarterly report is being
                prepared;

         b.     Designed such internal control over financial reporting, or
                caused such internal control over financial reporting to be
                designed under my 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 Partnership'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 Partnership's
                internal control over financial reporting that occurred during
                the Partnership's most recent fiscal quarter that has materially
                affected, or is reasonably likely to materially affect, the
                Partnership's internal control over financial reporting; and

     5.  I have disclosed, based on my most recent evaluation of internal
         control over financial reporting, to the Partnership's auditors and the
         audit committee of the board of directors (or persons performing the
         equivalent function):
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         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 the
                Partnership'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 the Partnership's
                internal control over financial reporting.


              May 15, 2007                      /s/ Joseph M. Jayson
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                  Date                          Joseph M. Jayson,
                                                Individual General Partner and
                                                Principal Financial Officer