need some motor home advice

Unless you have a desire to do some mohoming, after the family is gone, I recommend the rent and run scenario.

If you have ideas of using it personally, after the family's visit, - buy as big as you can.

While shopping around, let your nose be your guide in regards to mold, rot on the inside.
Aforementioned items, especially the ROOF, need to be professionally inspected before purchase.

Owned both land and sea yachts, found it very, very educationl, and rewarding.