Tenn. Code § 58-4-203
Before any part of any such appropriation shall be paid out of any county treasury, there shall first be filed with the county trustee of the county making the appropriation, plans and specifications of the proposed monument or building or library or other evidence of appreciation, with a detailed estimate of every cost and expense of the same; and it is further provided as an absolute prerequisite to the paying out of any part of any such appropriation that the persons receiving the appropriation, or any part thereof, shall give the trustee detailed vouchers approved by county monument or building commissioners and the county mayor in open court and personally receipted in writing by the payees and duly entered of record in detail in the books of the county clerk, in such manner and form as to clearly and definitely show for what purpose the money was paid and to whom, etc.
T.C.A. § 58-4-203