I'm with most of the other RV'ers. It's just dh and I and we find we have more than ample space. I do take a pressing board that is somewhere around 15x15", ample enough for most work and easily stored. Like memepat, I set up outside at the picnic table because it is much sturdier than the little fold down table we have with us. And like babies, it draws folks to start up conversations.
As to where I store my machine-when not physically on the road, it sits under the bench seat out of my carry case. When we do hit the hard top, I put it into the protective travel case and it goes under the bed or in the truck.
Have fun and safe travels.
Best,
deb in Maine