The Board of Highway Commissioners of said District will sell $20,000, or more of said bonds as it may determine upon receipt of bids, and bidders are invited to submit bids for $20,000, of bonds and for bonds in the amount of $30,000, or multiple thereof in addition up to the total $350,000 of bonds be numbered consecutively, and shall be issued as serial bonds. Bids must name the best terms at which bidders will purchase the said bonds. The bids must be accompanied by the approval of the Board of Highway Commissioners of the District, and the bid must be accompanied by a certified check for ten (10) percent of the principal sum of bonds upon which bid is made, payable to the Secretary of Potlatch Highway District. Should the District sell some part of said bonds less than the total amount bid for by any purchaser, the amount of such check over ten (10) percent of the principal bid for will be returned, but ten (10) percent of the amount of bonds sold to any purchaser will be retained by the District to apply upon the purchase price, or in the event of the purchaser refusing to take such bonds to be liquidated. The District will not be responsible for the amount of the bonds sold, nor for the amount of the bonds sold, nor for the amount of the bonds sold. 