If you have two AC units, you cannot run both on a 2000 watt (2 kilowatt) portable inverter generator. You'll be lucky to run one. In fact, many 15,000 BTU AC units will be hard pressed to run on 2KW even with a hard-start adapter on the AC unit. And if the AC is running, there is precious little power left for anything else. You need a lot more generator.
Solar is great...I'm a big fan of solar. I have 400 watts on my roof.
But the same is true of solar. If you need AC, especially two of them, even the best solar will run out of juice in short order.
Let's say you have a 15,000 BTU and a 13,500 BTU AC. If both are just running (not starting) they will draw about 13 amps and 12 amps respectively. Together 25 amps at 120 volts. Drawing from 12 volts, that's 250 AMPS!! There are precious few battery banks than can stand up to 250 amps draw, and if they do, they won't last long. And the fat wire to feed 250 amps may make you exceed your GVWR.
Again, solar is great for pretty much everything other than AC. If you have enough solar/battery/inverte
r it can even support a residential fridge.
Startup amps are much higher...for short periods. The hard-start kits help with that. But if both AC units try to start at the same time, you'll crush anything but a substantial generator.
So, if you plan to run both of your AC units, you need a generator that can deliver about 3000 watts continuous, and about 4000 watts for starting. Then add your other loads. If you're in the AC, one assumes the fridge is running and other draws are happening simultaneously.
Do some math: https://www.rapidtables.com/calc/ele...alculator.html
That 5500 watt Onan should do the job. 7000 watts is overkill. But that Onan is going to set you back $4500 or more plus installation. If installation includes propane lines, a lot more. Same with a gasoline fuel tank.
As an alternative, you might look into a portable inverter generator in the 5000 watt+ range. Put the genny in your pickup truck bed and leave it there. Get a short extension cable to allow your RV cable to reach comfortably. Or if you travel with a strapping younger person, get them to help you unload it.
A couple that might serve you well.
If you want "the best," this sweet Yamaha fills the bill: https://www.yamahamotorsports.com/ge...els/ef6300isde
I saw one of these in action on the toy-hauler tongue of a hybrid. From 20 feet away, it was difficult to tell it was running.
You could save a lot of money and have the power you need and a lot less hassle.
Comment: You don't mess around! That's one helluva first camper. Most of us start with pop-ups.