How much propane will I use?

Standard bbq tanks are 20lbs and if you have 2 on ur rv you could do some mods to put 2 x 30 lbs for more capacity. Most TT's have a threaded rod with a wingnut holding them down and a pvc cover to protect them. All can be changed out from rv or online vendors. Back in my tt days the 20 lb propane tank lasted month's with a mix of full hook ups and dry camping. Now with a 12 cu/ft fridge dry camping I use a 30 pounder every week or two depending on hot water and furnace usage. Fridge is still the smallest user of LP with furnace being worst. Also do you use your oven/stovetop a lot. A few more trips and you will figure out your average usage. Also you might want to ensure no leaks as our systems have a bad track record of leaking at the regulator etc.