When I bought my 8' Grandby it was set up to sleep 5: 2 on overhang, 3 on queen down; all east/west. With enough room in the back for a small fridge and one person standing (two if you're hugging).
If you are handy you could remodel a 6.5' or 8' with a table/bed in the front that sits 4 and...
Nope. Similar problem: there is not enough electricity going to farms to power planting and harvest. A couple of week window when a crop farm uses 80%+ of its energy.
We will need a massive generation, storage, and distribution rural upgrade for that to happen.
Diesel, gasoline, and natural...
One doesn't need that big a system. I run a 2.0 cu.ft. NorCold compressor fridge (my biggest energy consumer) on 200W solar and 208AH GC2 batteries. Usually at 80% in morning (Trimetric 2030 reported) and 100% by 1 pm.
POR-15 if you want it to last. Spray painting requires special equipment. You can apply it with a brush; paint outside (outgases isocyanates) with a breeze. One of my projects has lasted 30 years of hard use.
With any coating, prep is 90% of it lasting.