(1) Registration fee. The annual registration fee for registered and registered exempt interstate passenger transportation companies operating vehicles over the public highways of Washington state is:
(a) $10 For each motor vehicle operated by a passenger transportation company providing interstate charter or excursion service.
(b) $0 For each motor vehicle operated by a passenger transportation company providing interstate regular route service.
(2) Registration receipts.
(a) A legible receipt showing registration with a base state or the commission as a registered or registered exempt carrier must be present in each motor vehicle and the receipt is subject to inspection at all times by law enforcement agents and commission representatives. No person or firm may use a registration receipt issued by the commission other than the registered or registered exempt carrier to whom it was issued.
(b) All receipts issued for a calendar year expire on December 31 of that year.