Newbie here. Maybe wrong forum but here goes.

Being over 70 myself I would look at a 24 ft Class C with a full wall slide and a 18-24 ft TT with a slide. I would not want a corner bed especially if you have knee or hip arthritis. The short C's with a full wall slide such as the Chateau 24FE will have a queen bed and a bed overhead. Most of the small C's only have about 40 gals of FW and minimal storage compared to an A. A small TT will give you more FW 50-80 gals if you want to dry camp at NP's or SP's and more storage. Another benefit with a TT when not using it to camp you will have the truck to use as a second vehicle. The C will just sit most of the time in your yard or storage area. If you think you will use it more of the time and need more room then look at something like a Thor Vegas which will be about 25-27 ft, some have twin beds and some have full wall slides. Good luck in your search.