Consistent with Section 5.04(j) of this Revised Charter and except as otherwise provided in this Section, the City Manager shall award and execute all contracts on behalf of the City.
      Council, by ordinance, shall establish a threshold amount, notice provisions and other procedures for competitive bidding. When any contract for the construction of a public improvement or the purchase of equipment, supplies, or materials is estimated to exceed the threshold established by Council, the contract shall be competitively bid. Council shall award a contract to the lowest and best bidder, provided that Council may reject any and all bids in whole or by items. No contract shall be divided to avoid the requirements of competitive bidding.
      By a vote of no less than five members, Council may waive the competitive bidding requirement if the statutory or common law of the State of Ohio does not require competitive bidding; if Council determines that an item is available and can be acquired only from a single source; or if Council determines that a waiver of the competitive bidding requirement is in the best interest of the City.
      Contracts for professional services shall not be subject to the competitive bidding requirements of this Section and shall not require authorization by Council if the current operating budget provides sufficient funding for the scope of services in any such contract.
      Council shall establish procedures for alterations or modifications of contracts. Modifications or alterations of contracts shall not require competitive bidding.
      No contract involving the expenditure of money shall be entered into or authorized by the City Manager unless the Director of Finance or designee shall first certify that:
      (1)   funds required for the contract are in the City's treasury or in the process of collection; and
      (2)   funds have been appropriated by Council for the specified purpose and remain unencumbered.
      The Director of Finance shall file and record the certification of availability and appropriation of funds in the accounting records of the City and shall furnish a copy to the vendor or contractor. Without the certification, a contractual obligation shall be void and unenforceable against the City unless recognized by Council as a moral obligation.