(1) All bids which require either formal or informal bidding shall be opened in public and read at the time and place specified in the notice.
(2) The awarding of contracts need not be upon the day of the opening of the bids but may be at a later date to be determined by the purchasing official.
(3) In order to assure that the bidder will accept and perform a contract under the terms of his or her bid, the purchasing official may require bids to be accompanied by certified check or surety bond furnished by a surety company authorized to do business in this state in such a reasonable amount as the purchasing official shall determine.