My wife and I are just finishing up a six month full time stint in our 1985 Airstream Sovereign
. We successfully kept our 500 amp battery set above 70% for the duration with the help of 2 older 50 watt pv panels and occasionally topping off with a campground's power. I gained most of what I know from extensive research and reading and based my batteries, charge controller, converter and inverter purchases on this information. What was right for me will probably not be right for you, which is why I do not detail my choices.
The best, most honest source of photovoltaic knowledge for RV'ers, in my opinion is Handy Bob's blog at https://handybobsolar.wordpress.com/
Along with some great advisors on Airforums with credentials, you should be up to speed in time.
Caveat: Handy Bob has seen a lot of stupidity in his time so he can sound angry. He has also seen umpteen vendors of batteries, pv systems and installers mislead their clients, so he trusts only a few proven entities. Read his entire blog before you even think about soliciting information from him.