Found a way to do what OP is asking. Took me 1-2 hours of online nothingness, and Ace Hardware treasure hunting. Get a basic door hinge. Mount on the inner door with bolts all the way through - not screw, but socket bolts so no thief with screwdriver can easily undo. The swinging part of the hinge will accept a standard combo lock. That lock will act as the “stop” between doors. See pics. I attached a little key ring to help pull it out when you attach the lock.
1 Like