I use my tanks a lot. For one thing I use my
furnace pretty regularly. I do cook in my camper, but I also uise the propare mode on the frig pretty regularly. (I seldom camp in normal places)
But I also use them in a different way. I love bbqing. And of course these are the same tanks that my BBQ uses. What I do is that when I run out of gas for the BBQ I use the tank from the camper that I have been using and then get the empty one filled up in the near future. So I always have spare gas on site at my house and also have plenty on the camper.
I almost never actually do the swap thing as who knows how good of tank you will get with a swap. There are a lot of places that fill them any more. And since I have a spare handy I can go to a refill place. The swap places are open more but since I always have plenty, I can actually get them filled instead and keep the good ones. And that is almost always cheaper.
Not exactly on point here, but something to think about.
Now when storing them an OPEN AIR BARN sounds reasonable. As long as you have no ignition sources there. I regularly see them stores in closed in places in inhabited areas. Utility closets seem popular.
Electrical rooms in businesses seem even more popular. :-( I also worked a job about a year ago that tells you why. Apartment complex that has regular cook outs for the residents. They were storing a large 2 tank grill and the tanks in the computer room because "it is handy and besides it is secure and we don't want anyone stealing them". Nobody was hurt, luckily, but apparently one was leaking just a little bit. They think a cooling fan from one of the servers ignited it. Hard to tell, The tanks, grill, EXPENSIVE COMPUTERS, and the room ended up missing. They got a big fine and then had to rebuild it and had to pay for me to spend a lot of days figuring out how to trace the wiring to the rest of the complex and get it hooked up or replaced. SO OPEN AIR WITH LOTS OF VENTILATION AND NO SOURCES OF IGNITION WOULD BE NEEDED.