I rent an outdoor bike locker and in the last decade never had a problem with theft or vandalism. My locker is located near the entrance to my downtown office building and the building has 24 hour security guards that roam the perimeter of the building every hour or so. The locker door is pretty solid and has a substantial built-in lock.

I routinely leave my bike overnight in the locker without any worries.

The locker is also very convenient. In addition to the bike, I also keep a spare tire and tube, chain lube, a floor pump, rag to wipe my bike down after a wet ride, and leave my helmet and gloves in the locker.