Ignoramus10092 fired this volley in
:

I talked to the UPS driver who serves the area, I will put a
combination lock on this cage, tell him the combination, and will put
outgoing parcels in it. If he sees packages in there while passing by,
he will open the cage and get the stuff. I will keep propane there
also.

And he will occasionally forget to or fail to properly lock it, and your
propane will be gone.

If you do a lock, make it a 'double closing' affair. The door will be
half-open AND locked when he gets to it. After putting your packages in,
he closes the door, and regardless of whether he locks the padlock again,
the door locks tight with a mortised key lock.

LLoyd