(a) No individual shall serve as a member of the county board of tax assessors who:

(1) Is less than 21 years of age;

(2) Fails to make his residence within the county within six months after taking the oath of office as a member of the board;

(3) Does not hold a high school diploma or its equivalent. An individual who has held an equivalent responsible position of employment for a period of five years shall not be required to meet the high school education requirement provided in this paragraph. The commissioner is authorized to specify by regulation the types of employment qualifying as equivalent responsible positions of employment under the terms of this paragraph;

(4) Does not have at least one year of experience in appraisal-related work. The successful completion of 40 hours of approved appraisal courses as provided for in subsection (c) of this Code section, taken either prior to appointment or within one year after appointment, may be substituted for this experience requirement;

(5) Has not successfully completed an assessor examination to be administered by the commissioner or has not successfully completed at least 40 hours of approved appraisal courses as provided in subsection (c) of this Code section; and

(6) Does not successfully complete at least 40 hours of approved appraisal courses as provided in subsection (c) of this Code section during each two years of his tenure as a member of the county board of tax assessors.

(b) The requirements of subsection (a) of this Code section shall not apply to any member of a county board of tax assessors who was properly appointed and who was serving on January 1, 1973, until such time as the term for which he was serving on January 1, 1973, shall expire.

(c) Approved appraisal courses shall be courses of instruction covering the basic principles of appraisal and assessing of all classes and types of property including instruction in the fundamentals of Georgia law covering the appraisal and assessing of property for ad valorem tax purposes as prescribed and designated by the commissioner. The commissioner shall develop and administer courses of instruction designed to qualify applicants or tax assessors under this Code section; and he may contract with any professional appraisal organization or firm or institution of higher education in this state to provide the necessary courses of instruction or any part of any such course.