-1 for locked chests. We have towny for a reason.
-1 for gate. Just put a damn door.
-1 for ladder alternative. Put a damn ladder.
~ @Klitch
Basically this. You can always set your plot perms to off and/or make a chest shop sign.
For doors, set your plot perms off.
The last one, I really don't think it's needed, ladders and stairs work just fine. :)