You can go nuts with electrical power for the trailer, solar panels, battery banks, inverter, shore power inlets, etc.
Or you can keep it simple and get a small (2000 watt) inverter generator and have a couple of extension cords to plug in to. Expand later if you feel the need.
The Harbor Freight generators are getting pretty good reviews. I own Honda, so I’m not in a position to review the HF machines, but the guys on the RV forums seem to like them.
Just be sure to get an inverter generator. They are quiet and won’t rouse the anger of your neighbors.
A 2000 watt generator will run any modeling related power tool, maybe several at once unless one is the soldering iron. My Honda will run the air conditioner in the camper, but nothing else along with it.
Another handy option is cordless power tools. The Milwaukee M12 line has a cordless soldering iron, rotary tool, tire inflator, drills, saws, and much more. Step up to M18 and you can get a table saw, chop saw, even a chainsaw. Use the generator to recharge those batteries.