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                                                                    EXHIBIT 31.2

                                 CERTIFICATIONS

I, Christopher J. Papa, certify that:

     1. I have reviewed this annual report on Form 10-K of Post Properties, Inc.
        and Post Apartment Homes, L.P.;

     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 registrants as of, and for, the periods presented in
        this annual report;

     4. The registrants' other certifying officer and I are 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 registrants and we 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
           registrants, including their consolidated subsidiaries, is made known
           to us by others within those entities, particularly during the period
           in which this annual 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 registrants' 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 registrants' internal
           control over financial reporting that occurred during the
           registrants' most recent fiscal quarter that has materially affected,
           or is reasonably likely to materially affect, the registrants'
           internal control over financial reporting; and

     5. The registrants' other certifying officer and I have disclosed, based on
        our most recent evaluation of internal control over financial reporting,
        to the registrants' auditors and the audit committee of the registrants'
        board of directors (or persons performing the equivalent functions):

        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 registrants' 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 registrants' internal
           control over financial reporting.

March 15, 2005

<Table>
<S>                                                     <C>
POST PROPERTIES, INC.
a Georgia corporation
                                                        By: POST APARTMENT HOMES, L.P.
/s/ Christopher J. Papa                                    a Georgia limited partnership
--------------------------------------------               By: POST GP HOLDINGS, INC.,
Christopher J. Papa                                            a Georgia corporation, its
Executive Vice President and                                   sole general partner
Chief Financial Officer

                                                        /s/ Christopher J. Papa
                                                        --------------------------------------------
                                                        Christopher J. Papa
                                                        Executive Vice President and Chief Financial
                                                        Officer
</Table>

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                             Post Properties, Inc.                           126
                           Post Apartment Homes, L.P.