Tennessee Code Title 5. Counties § 5-21-118

(1) The contract, purchase, or any obligation of the county for supplies, material, equipment, contractual services, rental of machinery, buildings, or equipment, transfer of materials, supplies, and equipment between county offices or agencies;

(2) Supervision of storeroom or warehouse;

(3) Contracts for building construction and the purchase of land;

(4) Public sale of all surplus materials, equipment, buildings and land; and

(5) Any other created obligation of the county.

(c)(1) Upon the recommendation of the committee and approval of the county legislative body or as authorized by the county legislative body, a separate purchasing department may be established with a person hired as purchasing agent for the county.

(2) In the event a separate purchasing department is established and a purchasing agent is hired, all duties and responsibilities relative to purchasing shall be removed from the director.