Here's my experience with battery use . I do not have solar panel, I do not take a generator with me. I have run down the battery to dead on one occasion for a three day weekend (FURNACE!!! and Incandescent Lights). At the time , I had only one battery, I now have 2.
More recently, I have gone 3 nights, 4 days, using only battery power (2 x 12VDC deep cycle batteries in parallel). Used the furnace on 2 of those nights. The furnace is the biggest 12 volt power user. I have all LED lights on my Pod now, so use from those is minimal. The refrigerator is very low power usage when running propane, just the control board. When I was done camping my batteries read 11.4 volts.
You "can" run the microwave if you install a DC-AC power inverter of more than 1500 watts. BUT this will really use a lot of power, even for a few minutes. I have a small 200 watt inverter for powering the LCD TV (22 watts), also used for charging my cell phone (usb charge port built into it). I unplug the TV and shut off the inverter when not using it.
There is no 120 VAC unless using a generator (2500+ watts for A/C, 2000 watts for Microwave only typical, and charging battery)
Get a second battery , use a 4 position marine grade battery switch ( Battery 1, Battery 2, Battery 1+2, OFF ) Run the batteries in parallel when using them.
Get LED Lights, get rid of the little incandescent bulbs if your pod comes with them they are huge power eaters at night.
The furnace eats through battery power running the fan. I wish there was a more efficient way to heat the camper in sub 40 degree weather (it happens in Northern Vermont in Spring and Fall). I am looking into adapting the propane water heater to get a hydronic hot water loop running under the mattress. Still investigating this. It's been doen before, I'm not sure it's worth the effort or what the result would be like.
Solar can replace some of the power used , depends on how much you actually use the 12V system.