(1) The County may join with other units of local, State, or Federal government in cooperative purchasing plans pursuant to Chapter 39.34 RCW or any other authorizing statute to the extent permitted by State law.

(2) Any such plan shall provide that each of the participating units of government shall be separately invoiced by the vendors or service providers for purchases made under such plans and that the County shall not be obligated for any purchases other than those required for its own use and supplied pursuant to the request of the County.

(3) Any proposed plan shall be approved by the Board.