A county public building authority is formed when three or more people who are qualified to vote in the county apply to the county legislative body to incorporate a public building authority and the county legislative body approves the application. A public building authority is a public nonprofit corporation and an instrumentality of the county that may be used in the financing, construction, maintenance, leasing or disposition of public buildings and infrastructure. The board of directors of the public building authority is appointed by the county mayor subject to confirmation by the county legislative body in a number not less than seven who serve terms of six years except for the initial appointments to terms of two, four and six years to create staggered terms. A director of a county public building authority cannot be a county officer or employee. The directors serve without compensation except for reimbursement of expenses. A municipality may also form a public building authority. T.C.A. § 12-10-101 et seq.