Read the FAQ's on the opening page of the B forum. Several times is better.
Be prepared to travel to look, and be prepared to be disappointed.
Go ahead and buy a tire pressure gauge that goes to 120 PSI (you'll only need 80, but inaccuracy is most likely at extremes of the scale).
Tell us if you're looking used or new; big difference in hunting techniques.
Whichever, lose the salesdroid or owner; get into the van with your SO and close the doors. Simulate various activities: take a drink out of the reefer; shower; take a leak; do a technicolor yawn (barf) kneeling at the toilet; move from front to back; sit in the front seats for a while as if driving; turn the front seats to face the rear; lounge & watch TV. Start the generator; live with it running for at least 15 minutes. Start the furnace. Listen to both.
Jim, "Mo' coffee!"