If any department, board, commission or agency of the county government shall purchase or contract for any goods, materials, supplies, equipment or services, or shall sell any obsolete or unusable materials or equipment contrary to the provisions of sections 383B.141 to 383B.151, such order, contract or sale shall be void. The head of the department, board, commission or agency shall be personally liable for the cost of the order or contract and for the reasonable value of the materials or equipment sold. If the order or contract is already paid for out of county funds, the amount thereof may be recovered in the name of the county by appropriate action. Property sold contrary to the provisions of sections 383B.141 to 383B.151 or the reasonable value thereof may be likewise recovered in the name of the county.