The certificates issued by the department shall be conclusive evidence to all parties interested of the facts stated therein and shall form the basis of settlement between buyers and sellers unless otherwise specified by contract; provided, the department shall have the right upon reinspection or otherwise to cancel and revoke any certificate and issue a new one in its stead, and every certificate of grade shall be subject to appeal as provided by law; and in either case such new certificate or the appeal certificate shall in such event be final and binding between the parties.
§ 411.170, RSMo