Ohio Rev. Code Ann. § 1710.11

The board of directors of a special improvement district shall adopt written rules prescribing competitive bidding procedures for contracts awarded under this chapter. The procedures may differ from competitive bidding procedures applicable to the participating political subdivisions of the district or those provided in Chapter 735. of the Revised Code. The rules shall provide for advertising for bids and specify the bidding procedures to be followed, and may specify conditions under which competitive bidding is not required and other conditions such as establishing a dollar limit per contract or specifying particular parties to a contract.