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
         September 30, 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.

              November 13, 2007                 /s/ Joseph M. Jayson
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                    Date                        Joseph M. Jayson,
                                                Individual General Partner and
                                                Principal Financial Officer