Pondering the same issue as I plan out my build...
Certainly the RV Latch that bigbendhiker mentioned would be the most elegant. Perhaps the simplest would be to add an inside door latch,
and locking the outside latch closed when camping in it. Of course, if someone is hell-bent on locking you in, they could wrap a lock or wire
around the door handle and cam bar... and of course, they could do that even if you installed an additional hasp to lock the cam bar in the open position...
Seems to depend on factors such as how trusting you are (I'm probably too much so), if you use your CT for storage of valuables (I'm guessing the cam bar lock would be more secure than the RV lock ???)
and where you would actually camp inside it (e.g., semi-secure campground vs public street, parking lot, etc.).


