First I’ll point out we are super low energy users. No micro, tv, have led lights usually only a couple of this are ever on. We have one 160W roof mounted solar panel. We are boondockers and even in a Nat Park site we don’t use a hookup.
At home our camper is under a CalMark cover which is fantastic by the way. Apparently we keep a charge even under the cover (we’re in norther AZ).
We’ve never had a power problem with this setup (2 Lifeline GPL-4CT batteries). I had an extra “portable” zamp panel, but never used it and sold it. Hope this is some help in some way.