HELP! Needed to know this yesterday

We use a propane lantern after sundown before going to bed and it keeps our 26' trailer fairly warm. we also use individual LED lights for reading. While sleeping we have extra blankets and keep the bedroom door closed as our body heat keeps the bedroom fairly comfortable. We sometimes wear socks when we sleep. In the morning I light a propane heater (mounts on a single green 1 lb can) to take the chill off (1-2 hours when in the upper 30s). We never use the furnace when boondocking as it drains too fast with the furnace blower. The house battery (we have 2 12v in parallel) is reserved for water pump and frig control and we can go a week this way. I do have a 12V 6A charger that I power from a 400W inverter that I use from my tow vehicle power outlet (cig lighter) and top off the batteries every couple of days. I do NOT need to run the tow vehicle engine to do that. It is better to use the top of the battery charge for quick recovery rather than deep discharge; too hard to recover from that.