2008 RZR. Bout to sell, tired of wasting time

have a 2008 800 RZR. first problem was the belt, it burnt up along with the ducts. we got those fixed up and still had issues and sent it to Polaris to be checked out. they said the clutch/throttle weren’t opening up and redid it all. came back and still sounded awful. it started cutting out really bad starts up fine and will run fine til warmed up then starts cutting out bad. so we replaced spark plugs, wire connectors, fuel pump, all for it to just keep sounding terrible. it know feels like no power and its trying to by all the loud noise. the passenger side I noticed becomes hot easy also- the air filter is brand new as well the entire thing has became a pain in the ass. I need some answers otherwise I’m bout to get rid of this money pit.