Dealers are required by LAW to state that they are so.
And I hope Rick understands that it is a violation of most states law to advertise a car for sale by a dealer, and *NOT* disclose that they are a dealer... To quote the blurb that's always in the auto section of the classifieds in the local paper...
Oregon Law requires individuals selling vehicles as a business to be licensed and to disclose in all advertising that they are dealers. If you encounter a seller who has not disclosed that they are a licensed and bonded dealer this is a violation of the "Unfair Trade Practices Act." Contact the Oregon Department of Justice, [contact info removed].
Selling a vehicle, other than your own, without a dealer's license may be a violation of vehicle dealer licensing law. Contact the Oregon Department of Motor Vehicles, [contact info removed].
Because your ad is reaching Oregon residents, you must comply with Oregon advertising laws. (Unless you specifically state that you will not sell to Oregon residents.) But, you still have to comply with similar laws in other states, including your own home state of Washington, which has an almost identically worded law.
Indeed, in your previous posts here on PriusOnline, you do state that you are a dealer, and by the current rules on PriusOnline, you must post only in the 'Dealer' forum, and you must disclose the dealer name and location.