Steve, your power consumption is really low. If you want to make sure of how long you can go why dont you leave the unit plugged in at home for a couple of days to get your battery up to the charge it would normally have when your going to go on a trip.
Then unplug it.
Put a couple of cokes in your fridge, and let it run on propane and your battery alone.
Leave one of your lights on, full time, and simply check every day to see when the fridge shuts down.
Basically that duplicates what your usage would be.
With only a fridge, CO detector and a light, whether or not your in the unit changes nothing.