I saw a car I wanted once, went home did my homework, came up with a price I thought was fair. Went to the bank and got a certified check made out to the dealer for that price! When the manager saw it, (cash in hand) he didn't want to let it go! I got it for that price.
So don't give them any money or sign anything until it's fixed and ready to go out the door. If you do you loose all your leverage.
If possible stay a night in the camper at the dealers lot to really make sure it works and you can work it.
Good luck, remember you do not have to buy that camper now.
