I know a lot of people rely on the “tank selection” valve as the “shut off” valve on the RV to keep propane from leaking from the tank. In theory this should work. A loose connection or defective hose to the “tank selection” valve may let propane escape. This situation is not only expensive due to the loss of propane but it is dangerous.
I recommend shutting off the propane valve at the tank when not in use. It may take a little more time during setup, but it is safer and may prevent loss of propane while the RV is stored. This goes for trailers and coaches.
I know of situations where RVers have inadvertently left the refrigerator on AUTO when they shut-down the RV for storage only to find out the propane tank was drained while the refrigerator switched to propane use “automatically”. The best way to prevent a loss of propane under this circumstance is to close the propane valve at the tank. Even if the refrigerator is left ON in the AUTO position, the propane will not be released to the refrigerator.
It does not take much time to secure the RV and one key act is to make sure you close that propane valve at the tank.