I need some help!!! (deciding on a rv)

Ok so my family and I are taking our first rv trip this summer and we are trying to find an rv to purchase. We thought about renting but the prices we are seeing are in the 5000 plus range and then extra for mileage. Don't laugh but we are doing a 9,000 mile, 35 day tour of the US. Yes we are crazy. I figure if we don't like it we can just come home. Ok so I've looked at what seems like 1000's of rvs in the 88' to 02' range. We know we want a class c with queen or double bed in back and the couch/2 captains chairs up front. something between 26 and 30'. The problem i'm having is figuring out why a 92' with 85,000 miles is 10,000 and a 99' with 43,000 miles is 9,000. A few things I know that are important- good ac, working refrig gas/elec and a good generator and newer tires. What else do I need to look for and how can I tell what brands are higher end than others? Is their a buying guide in the forum? Any help would be much appreciated. JUST TELL ME WHAT TO BUY!!!! LOL...

Price differences between similar RV units follow the same logic as cars. It's what the market will bear and the perceived quality. Said another way: a Mercedes and Ford Focus, both could have 4 doors, same mpg but very different pricing.

In comparing the 2 units of different ages you sited, are they both made by the same manufacturer?

Yes. In general, buying is cheaper than renting.