Just an observation from my personal experience. Sales people can come up with the numbers that make things look really good. If you want to get the scoop on the RV you are looking at, gain the confidence of a mechanic. (although at our auto dealership they like to be called technicians) They can answer things about the technical aspects such as 'what problems have you had the wiring, (or plumbing, or suspension etc) on this particular model of coach?" They can tell you about size of tanks, dependability of pumps and complaints that customers have had.
On the chassis of motorhomes, these RV techs may not be your best source, but I found a truck mechanic that loved Cummins engines. He saved a friend of mine a headache and a pile of money. I got him to check out a coach my friend was looking seriously at buying and after checking the coach chassis over thought there were at least two injectors going out. Sometimes it is easiest to go around a salesman than to have to figure out what he is NOT telling when you start asking questions.
