(A)(1) Subject to division (C) of this section, the board of county commissioners may enter into an agreement with the legislative authority of any municipal corporation, township, port authority, water or sewer district, school district, library district, health district, park district, soil and water conservation district, water conservancy district, or other taxing district, or with the board of any other county, and such legislative authorities may enter into agreements with the board of county commissioners, whereby the board undertakes, and is authorized by the contracting subdivision, to exercise any power, perform any function, or render any service, on behalf of the contracting subdivision or its legislative authority, that such subdivision or legislative authority may exercise, perform, or render; or whereby the legislative authority of any municipal corporation undertakes, and is authorized by the board of county commissioners, to exercise any power, perform any function, or render any service, on behalf of the county or the board, that the county or the board may exercise, perform, or render. The board of county commissioners may enter into an agreement with the board of township trustees of any township within the county, whereby the board of county commissioners or any county official designated by the board, purchases at the request of the township any materials for the construction, maintenance, or repair of any township road or for the maintenance or repair of any township building, and sells the materials to the township at the cost to the county, which cost shall include the purchase price and any expenses incurred in such purchase, providing the amount involved does not exceed one thousand dollars.

(2) Upon the execution of an agreement described in division (A)(1) of this section, and within the limitations prescribed by the agreement, the board of county commissioners may exercise the same powers as the contracting subdivision possesses with respect to the performance of any function or the rendering of any service, which, by such agreement, it undertakes to perform or render, and all powers necessary or incidental thereto, as amply as such powers are possessed and exercised by the contracting subdivisions directly; and the legislative authority of any municipal corporation may exercise the same powers as the county possesses with respect to the performance of any function or the rendering of any service, which, by such agreement, it undertakes to perform or render, and all powers necessary or incidental thereto, as amply as such powers are possessed and exercised by the county directly. In the absence in the agreement of provisions determining by what officer, office, department, agency, or authority, the powers and duties of the board shall be exercised or performed, the board shall determine and assign such powers and duties. In the absence in the agreement of provisions determining by what officer, office, department, agency, or authority, the powers and duties of the legislative authority of the municipal corporation shall be exercised or performed, such legislative authority shall determine and assign such powers and duties. Sections 307.14 to 307.19 of the Revised Code, or any agreement authorized by those sections, shall not suspend the possession by a contracting subdivision of any power or function exercised or performed by the board, or the possession by a county of any power or function exercised or performed by the contracting municipal corporation, in pursuance of the agreement. Nor shall the board, by virtue of any agreement entered into under this section, acquire any power to levy taxes within, and on behalf of, a contracting subdivision unless approved by a majority of the electors of the contracting subdivision.

(B) Subject to division (C) of this section, the boards of county commissioners of any two or more counties may contract with each other or by contract create any joint agency to exercise any power, perform any function, or render any service which any board of county commissioners may exercise, perform, or render.

(C) No board of county commissioners shall enter into any agreement pursuant to division (A) of this section or form a joint agency pursuant to division (B) of this section to exercise, with regard to public moneys, any investment powers, perform any investment function, or render any investment service on behalf of a contracting subdivision or its legislative authority, or, with respect to a joint agency, another board of county commissioners.