Each peddler, hawker, or itinerant vendor, selling goods on their own behalf to purchasers for use or consumption, must display prominently, in connection with their business, the Certificate of Registration issued by the Department. If a vehicle is used, the Certificate must be affixed conspicuously thereto. If no vehicle is used, the Certificate should be attached, in such a manner as to be readily visible by the public, to the sample case or other container used by the peddler, hawker, or itinerant vendor in transacting their business.
Ill. Admin. Code tit. 86, § 130.1990