Offering items for sale at prices that seem too good to be true, or are heavily discounted, is not a policy violation. This is just correctly suggested to buyers as a possible warning sign of fraud.

You haven't understood how eBay works. At any time there are literally millions of items for sale here, including probably thousands of obviously (or not obviously) fraudulent listings. eBay doesn't attempt, or even claim to attempt to scrutinise listings or prices - least of all for 16 year old motorhomes!

To understand the reality of eBay, read section 2 of the legal agreement. eBay specifically warns buyers that they do not guarantee the quality of items sold here, or that they will be truthfully described, safe or even legal. If anything should be a warning sign for buyers, this is it.

Motor vehicles are even excluded from their own, 30 day money back guarantee. The only safe way to buy is not to pay anything, not even a deposit, until you have seen and inspected the vehicle. Then pay by cash or other safe method. By the way, you are not the first buyer to be referred to an address where a confused householder has had multiple "buyers" turning up to collect the same, non-existent vehicle. One had so many that he produced an information sheet to explain how to report this fraud to the police.