Go over it with a fine tooth comb and make sure everything works BEFORE you sign on the dotted line. Make a list of any thing that isn't right and have them fix it first, once they get their money you are no longer their new best friend and getting things done won't be nearly as simple.
I think there may be a list here on the forum on what to check, but I can't find it.
FWIW we had only one real issue with our Coleman, the A/C wasn't installed properly. It was promptly fixed. There have been several smaller issues that I just took care of myself rather than waste time not camping while waiting on warranty work to be scheduled.