All the exterior compartment doors have a key lock on one side and a thumb latch on the other. Some RV owners say not to change the locks because if someone wants in they can open the thumb latch then bend the thin aluminum door open. One fix is to replace the thumb latch with another lock but this is expensive for all the doors and cumbersome to operate. So I came up with an idea to connect the two latches.

First door latch idea using a chain

Second door latch idea using a rod