The bonds may be issued and sold for not less than their par value, but otherwise as the board determines. Before selling any bonds, or any part thereof, the board shall give notice inviting sealed bids in such manner as the board may prescribe. If satisfactory bids are received, the bonds offered for sale shall be awarded to the highest responsible bidder. If no bids are received, or if the board determines that the bids received are not satisfactory as to price or responsibility of the bidders, the board may reject all bids received, if any, and either again give notice inviting bids or sell the bonds at private sale.