My boat got broken into last summer.
Bunch of stuff stolen. Fortunately, the only damage was that the southco door lock was busted.
So, I decided to do something which would clearly indicate that screwing around with my boat was a waste of time. Using extra inside latches doesn't accomplish that. They will only try & force the doors harder, until something breaks.
So, this is simple & cheap.
In the photo, only one lock is shown, but I added another one at the opposite end of the wood piece.
Plus I painted it white, and affixed a large alarm sticker.
Message "find another boat"