Sec. 5. Subject to IC 8-23-7 and this chapter, all sales of property belonging to a state agency, other than property:
(1) on which allowance is made on another purchase with the written approval of the commissioner; or
(2) whose disposition is otherwise provided for in this chapter;
shall be conducted by the commissioner only under IC 5-22-22-4 or IC 5-22-22-4.5. All sales must be made to the highest responsible bidder.