I would say that you need to do a complete check up as well, Put pressure to the water system, check out the electrical, fill the fresh water tank (At least a few gallons) and make sure the pump works. Check out the holding tanks to make sure rats have not holed them (Believe me it happens. Thankfully not to my rig, but to another parked nearby at one time)
Have a qualified tecnician check out engine and drive train, INSPECT THE ROOF, SERIOUSLY INSPECT THE ROOF, Check out all features, slides, electric steps, leveling jacks, etc.
Sometimes, espically this year, someone buys a MH thinking of the great times back when gas was <2.00 a gallon and now seeing >3.00 looming they basically let it set, and sometimes due to the cost of maintaining /fueling their 4-wheel vehicle (Car) do not make payments
This can mean a great MH at a bargain price.
On the other hands, sometimes they move in, abuse the blazes out of it, don't maintain it, forget to ever go up on the roof which is now midlewed and rotted and leaking like a sive, and about to cave in, and... Well you get the picture