(a) The local governing body of a municipality or county electing to enact an ordinance to provide for the protection, enhancement, perpetuation, or use of historic properties or historic districts shall establish or designate a historic preservation commission. Such local governing body shall determine the number of members of the commission, which shall be at least three, and the length of their terms, which shall be no greater than three years. A majority of the members of any such commission shall have demonstrated special interest, experience, or education in history or architecture; all the members shall reside within the historic preservation jurisdiction of their respective municipality or county except as otherwise provided by subsection (b) of this Code section; and all shall serve without compensation. In establishing such a commission and making appointments to it, a local governing body may seek the advice of any state or local historical agency, society, or organization.

(b) The local governing body of a county and the local governing body or bodies of one or more municipalities lying wholly or partially within such county may establish or designate a joint historic preservation commission. If a joint commission is established, the local governing bodies of the county and the municipality or municipalities involved shall determine the residence requirements for members of the joint commission.