I use one Renogy solar panel for my Airstream. I mounted on the back window and drill a hole for the cable to run to a 20 amp solar charger. The solar charger uses a separate battery for its battery input to the solar charger. I could replace the solar charger and battery with my AC200 but I lost my last solar generator due to the heat in the summertime. Be careful.
Now about the solar panels, when you mount them on the roof, you will need insulation between the flex panels and the roof. There are videos about the damage to the roof when the panels are taken off panels.
Harlan
I’m having trouble finding the panels I’d like: 30-35 volt each for a combined voltage of at least 70. Most panels are in the 18-20 volt range and I prefer to have only two panels rather than four.