Not going to happen, unless you go for something like a large van converted and sold as a race van, but it won’t be much of a motorhome, I started looking for a MH last year, but didn’t want anything too big/expensive and garage size was an issue for me too, I ended up buying a Mercedes Sprinter based Hymer 520S and a BMW 310R to go in it! But even then it only just goes in and weight is not ideal, but legal.