The City Manager shall make all purchases on behalf of the municipality. Purchases may be made simultaneously with purchases by other governmental bodies and in cooperation with their officers. Amount of purchases shall be determined by R.C. § 735.05 regulating advertisement and the receipt of bids in writing. An exception in the case of emergency which shall not admit of delay is created in which such requirements of advertisement and receipt of bids in writing can be waived. In any such case the City Manager shall report the facts to Council at its next meeting. After the receipt of bids Council may authorize the City Manager to make the purchase from the bidder who in its judgment offers the best proposition for the municipality considering quality, service, adaptability to the requirements of the municipality and price, or may direct the rejection of all bids.