I see I should have explained more :).
We don't have a standard RV -- it's a self-built project, and we don't have a generator. Didn't think we would need one :/.
We'll be in a dense city. Not a place where people have lawns or lawnmowers.
The batteries are AGM, so no concerns about gassing. They are 2x50aH and 1x100aH, so they need quite a few hours to charge.
We could get a generator, but I really don't think it's realistic to run it for 5+hours...and it would have to be at night, mostly, as we will be using the batteries during the day.
It's not a construction job; I don't know what gave that impression. Some auto work and stuff, running hoists, etc.
@smkettner Is that a typo? Did you mean INexpensive? Or not?