I'm not a fan of buying anything used from a dealer, overpriced and you really have no idea how it was used before because they all lie. Your paying way too much for it, and you don't get anything special in return. Any dealer wether it be cars, trucks, tractors, or power toys make their most money on selling used stuff.
"Factory Certified" is one of the biggest scams going. Traded a car into a dealer before that I serviced myself, never once brought it to the dealer for anything. They say "factory certified" stuff has always been serviced by their "expert" techs. Well a few days later saw my old car on the lot with the factory certified sticker on the windshield...
Your best bet buying used is always from a private party sale. Tractors...Find one that was owned by an older home owner (like most of us on here that take good care of our equipment). Do some investigating and ask the owner questions. Look around their shop and property, what did he or she use the tractor for? How well is the rest of their stuff they own taken care of? Things like that are dead giveaways. If they own a ton of land and work it hard, you may want to walk away and find one that was a glorified lawn mower and not a land clearing rig. Your going to pay less than retail, and you will get a machine that was well taken care of and will last you a very long time.
Don't hate the orange because a dealer tried to shaft ya, they are tough to beat hands down.