I'm in the last-minute design phase while I wait for my trailer to come back from being sandblasted and sealed. I'm looking for a system that will serve both a boondocker and a city-slicker alike. Short term I'm going to be running a 12v system for the lights and vent fan, long term I want to have things like a fridge and a window-unit AC. My current thought is to completely separate the two systems, attach an automotive battery charger to the 110 system that charges the 12v battery when plugged in (switchable, of course) but I'd still be able to boondock with the 12v system off the battery. The fridge and AC would just be lifeless when off-shore.
Somehow it just seems too simple. Like this is exactly what everybody else already does, or that I'm missing something terribly important.
Any ideas?