All bidders shall prior to the date of public auction post with the board of land and natural resources a deposit of $500. The board shall refund to unsuccessful bidders such amount within two days after the auction. All bidders, prior to the auction, shall satisfy the board of their financial ability to conduct mining operations and of their capability to develop a mine. The successful bidder shall pay to the board the amount of the first year’s rental within two days after the acceptance of the bid by the board and the $500 deposit shall be credited against such sum. If the deposit exceeds the first year’s rental, the excess shall be refunded. All rentals thereafter are payable in advance once a year.