I know that you said you are not rich. Neither am I. But, you should probably have a electrician come out and check to see what the problem is. Tell him that you want a diagnosis and a estimate but not a repair until you think about it and save up some money. You will still have to pay him some money for this of course.
Not just because of the threat of fire but, you don't want to give your family a electric shock either !! Or worse.
It's a regular system just like in a house. You do not need to have a RV place take a look at it. In fact, most RV places don't have a licensed electrician around anyway.
If the first electrician you call says that he can't do it, then call another. Sooner or later you will find one that will at least give you a diagnosis and a estimate.