1. Any city and the county commission of any county contracting by authority of this law for the purchase of right-of-way over a bridge may pay the purchase price therefor when having funds therefor and proper conveyance of such right-of-way shall be made; provided, that payment shall not be made for right-of-way over a proposed bridge until after completion of such bridge in accordance with plans therefor.

2. The expense of preserving and maintaining the paving on and lighting and guarding the roadway or roadways covered by or subject to such a right-of-way shall thereafter be shared by such city and county proportionately to the amounts paid by them respectively of such purchase price; and any and all necessary expense of permanently preserving and maintaining such bridge so as it shall be sufficient and proper support for such roadway or roadways shall thereafter be borne by the owner of such bridge.