Start with the battery... it might be the only issue, then agaaaain, maybe not.
I have to tell you that this sounds like some friends.
Her story "As I was walking out the door he says there is a MH like we want on eBay"
His story "As she was walking out the door, I tell her there is a MH like we want on eBay, and if the price is low enough I'm going to bid on it".
When she gets home, he tells her they "won" the MH.
She get a little "testy".
The seller (a dealer) tells them, that if they don't like the MH, he will refund their travel costs, if they do, they pay for it.
They drove it home and both have loved it (mostly) ever since.