So you've made a full circle with solar. The previous thread led you to 100-something watt portable solar. Ok, 100W with 20A Viewstar PWM, $200 total. A no brainer.
Like I already said, buy some AH meter for $40 if you are not sure of your energy budget.
GT Power will do. Ops - it's $13, not $40. Or get Turnigy meter for about same cost, many people here use it though it is less accurate.
To save you some math. With no 120V devices, no furnace - you said it's Mr Heater, LED lights, camp showers, propane fridge, "short run" of Maxxair fan (6 hours a day at max speed?) - you need ~50 AH a day. Half of that if you don't run fan.
2 Golf Cart batts = 112 AH usable charge, so you're good for 2 days. 160W solar will make it 4 days. 320W solar will make it "forever" like the other member suggested, because solar harvest will match or exceed your energy needs. IF IT'S SUNNY.
No sun, less fan, 40 AH a day, ~ 3 days.
No sun, 4*GC = 225 AH usable, 40 AH a day, ~ 6 days.
Recharging any battery in 3 hours with generator - sorry, doesn't happen. People "think" they've recharged because a stupid green light on trailer OEM panel says "Full", but it's usually ~70-80%. To make it really full, you need either 24 hours on shore power (with a proper converter, not WFCO) - or solar. Or few hours on generator and then solar. On a sunny day and with a bigger solar you won't need any generator time.
