I know this may sound obvious, but you said you had a well with a panel. Do you have 220 already coming onto the property? Worst case you could add a 30amp circuit to the panel and you could run the coach with it including 1 a/c unit.
If you only have 110, you could get by with a small heater in the coach, but you’d have to run the generator for the a/c.
Since you are going to a static site, what about wind? you might find the technology is more advanced for wind to accomplish what you want to do.
If you want a good resource for your application, try RV.Net. There are people that have probably tried every application to go off the grid and will be willing to help. Good luck.
One last thing...if this is being set up for Hillary amd Bill to go on the lamb, disregard anything I said previously.
A wel that has been unused for years that will need decontamination, pretty much bleaching it as I understand, then the county testing the water and approving. Well pump’s probably no good by now. Site once had electric but it’s not near the road and was taken down for some reason, storm damage maybe? I’d have to install a panel specifically to power the well pump regardless of anything else, it would honestly be cheaper to do that than pay to have it run out there again. And, I don’t own the property myself. Family does. Probably could buy it reasonably cheap if I actually end up doing this, like it and can make it work.