i made my garage doors. 2” box. 2” angle for the crosses and clad in t&g. no locks accessible from the outside. as near as i can make it burglar proof....
The entrance gate to the alley that leads to the yard has a clever arrangement for the lock.
If you can picture a square hole framed by substantial box section steel giving very restricted access to a substantial padlock on the inside of the gate. Not enough gap to get an angle grinder in but just enough to get the padlock on albeit with some difficulty by putting your hand in.