Ohio Revised Code Title V. Townships § 521.05

(A) If the total estimated cost of any improvement provided for in section 521.04 of the Revised Code is fifty thousand dollars or less, the contract may be let without competitive bidding.  When competitive bidding is required, the board of township trustees shall post, in three of the most conspicuous public places in the township, a notice specifying the improvement to be made and the time, which shall be at least thirty days after the posting of the notices, and the place the board will receive bids to make the improvement.  The board shall accept the lowest and best bid, if the successful bidder meets the requirements of section 153.54 of the Revised Code.  The board may reject all bids.

(B) On accepting a bid, the board shall enter into a contract with the successful bidder for making the improvement according to specifications.  The contract shall not be for a term longer than ten years.