You might also get a list of RV manufacturers and stop to take some tours. That's where you'll really zero in on how their made. Elkhart, Indiana, for instance - depending on what you're looking at.
Full-timed for 16 Years . . .
Traveled 8 yr in a 2004 Newmar Dutch Star 40' Diesel
& 8 yr in a 33' Travel Supreme 5th wheel