For folks considering an RV purchase, here is a great resource for answering many of your questions:
Shady Truth about Buying an RV
The authors are full time RVers, and this is from their blog. Experienced RV owners will find a lot to agree with. Examples: The "we won't service you" scare tactic that dealers use to persuade you to buy from them, and "the buyer knows more than the salesman." It is short and to the point. Recommended reading.
BTW, they have great RV how-to videos, too.
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