Operating fridge on propane and battery usage

[MrGallegos]

I am planning on letting a friend borrow my TM while he works on building a cabin. However, there is no electricity on the property, and I do not have any solar or generator, so the only power will be from the TM 100 amp battery. The only thing he really needs, besides a roof over his head, is the refrigerator, so it will have to run on propane. Interior light use will be very minimal, and no water will be used from the TM, he will have water jugs and toilet will be an outhouse.

My question is approximately how long the fridge could run on propane? How much battery will be used, if any, to keep the fridge running? I am trying to get an estimated time that can be realistically be used before the battery gets too low to recharge.

I do [not] want to tell him 5 days only for the battery to die in 3, and I want to make sure the battery has enough power to work the brakes when I tow it back home.