You do have some options here, I'll explain through my own experience. I have a Weekend Warrior toy hauler that I bought without the installed generator, WW wanted another $3200.00 for the built it model. I bought a portable 5500W Generac with a 8HP Honda engine brand new at Cosco for around $700 (you do the math, at the time it was all I could afford). Being that it is 5500W it will run my AC, blender, microwave, and wifes hair dryer all at the same time, but it is a bit noisey. My trailer has a 35Ft shoreline connection so when out at Glamis I just drag the generator out away from the trailer (and others camped near us) it works well for me, but my next toy hauler will have a built in unit. Honda has a really nice model caled the EU3000 SUPER quiet, but pricey, and it will not run all of your stuff at once, but will run most of it and re-charge your batteries. You will also want to think about if you are going to run a 30A or 50A servive in the trailer. Regarding batteries, give some thought to running 6V batteries wired in series as opposed to standard 12V's wired in parallel, and possibly an inverter running off the batteries to run some of you electrical. They will give you better service and life. I just made the swith to 2 trojan T105 golf cart batteries in my trailer and last my trip to Glamis I did not need to run the gen to re-charge them. I see you post at glamisdunes.com, try a search in the rv tech forum there, tons of useful info. Good luck and keep us posted on your progress, oh I like the black / grey color combo - won't look dated in 5 years...