Welcome to the forum and congrats on your new coach.
Sorry to hear your mother has memory problems. If you haven't you might want to start recording some of her earlier memories. With todays technology it isn't that hard or expensive.
As for waxing your coach we use Rejex. We use it on all surfaces that are not porous including the glass. It isn't cheap but a good coat will last up to a year depending on your weather conditions. You will probably get a lot of suggestions.
As far as washing it we use Turtle Wax car wash soap.