I have 2- 6 volt deep cycle batteries. I use the 105's . I would call them T-105's but the the T stands for Trojan and I use Duracell batteries I got at Batteries Plus to save money. I only dry camp a few times a years for 3 days at a time; at the most; and this has worked for me for quite a few years. I have no problem making it for 3 days. In the summer running LED lights, the fridge set to propane, a couple of fans, and the TV for a few hours a day I never even get close to running my batteries down. If, in spring and fall, I need to run the furnace I have to be frugal and only run it at night setting it for 60 degrees. I use the oven to bake something before going to bed to preheat the TT.
May not work for everyone but, it works for me.
https://www.batteriesplus.com/search?q=t-105
