I have the opportunity to purchase a 21' Tail-Gator year 2003. It is in fair/good condition considering its age. Everything works, no damage or leaks. Will need new tires as current tires are old (I don't trust old tires not matter how much tread they have). Seller is asking $5k. I think this sounds like a steal but I've never bought a trailer before. I go to look at it this weekend. Any critical questions to ask, things to look at?