I have a few well placed free spots I'll stay at. But with conditions...one is that it will not remain hot all night and have to run the generator/air conditioner long after dark. Always good to check here or on the road for tips on your route. I too prefer restaurants or Walmart so I can kill some birds with one stone. I do not like rest stops for more than a brief rest. I don't want to take spot from trucker and they're noisy. I've seen truck parking completely full at times.
In general I'd prefer to find cheap rvpark. Just recently stayed at one near Blythe CA for about $20 per night on Passport America. Power, dump station etc.
At least what I've seen, in the great open parts of the USA there are quite a few simple, non resort type RV parks with pull-through sites. Often the rates are quite low due to location. Check out Passport America for your travel area and see if any of those parks would work for you. Check "notes" and cross check reviews to see if acceptable.
Also check public campgrounds..sometimes these are very reasonable. Especially in low-tourist areas. You can re-use the good spots on new vacations.
