I would get a small B or C class and learn to drive it and operate everything. Start with short trips to see how it goes. Not sure I would take the boat. Maybe go somewhere you can rent a boat instead so you won't have the upkeep. We met a couple in NC and his wife had dementia and they traveled in a Class A. He had a golf cart and stayed in parks that allow him to ride around with his wife on the cart. Just one thing that will be an issue. As it progresses you won't be able to leave him alone at all. So things like going to the grocery store when you travel will be challenging. Hopefully you will have many years before that happens. God Bless.