This is a buyer's market for product mobiles. Last time it was the "other" Kissmobile and now it's the "other" Mufflermobile (not to be confused with this Mufflermobile):
She can be yours for $7,800.00 according to this eBay auction. I'm not sure what business it promoted before (and the auction is somewhat vague on the topic) but it has plenty of room to paint your muffler business' logo!