I had two things to consider on getting setup with a generator. One to run the whole 30A Electrical system or a smaller portable generator to just run my on-board converter/charger to charge up a bigger battery bank that will run just a few of things we might want to have running when camping off-grid...
With this in mind I went with the smaller portable generator which sets secured in the tail gate corner of my truck bed...
I beefed up my converter/charger and added more batteries right after I purchased my OFF-ROAD POPUP trailer with the thought in mind to have eough batteries to run through one day/night run off the batteries. Than at 8AM each morning when allowed to run my portable generator I can recharge my batteries back up to their 90% charge state in about a three hour generator run time and this will let me do all of this all over for the next day/night run off my batteries. This involves me having a Power Inverter to produce some 120VAC for a few of my low wattage things like the Home Entertainment setup etc... The other necessary items run off of propane or battery...
This is what we have been doing since 2009 on my 255AH battery bank and it is all second nature to us now when camping off-grid.
For us not having to run the generator for real long time runs makes for a very quiet camping experience and doesn't bother other folks camping near us at all... My little Honda 2KW generator is so quiet I can be leaning up against the truck and not hear it if I have the tail gate closed haha...
This is what we still do today here with my smaller camping setup... We are not into using the RV for Travel modes - Just for camping back off trail and in the high country within a couple hundred miles of us here in Virginia.
This will work for motorhome camping as well but I am pretty sure if I had a motorhome setup with a built-in generator I probably would keep the larger generator that would run the whole 30A electrical system... There is problems associated with both built-ion and portable generators trying to blend in with the other camp ground users...
Roy Ken