In case it hasn't been brought up in this thread or another, for those thinking about storing supplies in a public storage unit keep the following in mind. At least in my city (and I'd gather most others) burglaries against public storage units has been steady and in some cases increasing. In several reports I took people kept firearms, ammo, and other similar type of items inside.
Most of the large corporate chain types may or may not have video surveillance mounted only at entrance/exit areas. In most cases they're not HD, and quite frankly it wouldn't matter since you couldn't determine if a vehicle/person was connected to the crime anyways. The public storage units are just secured by a padlock, something easily enough defeated by a pair of cheap bolt-cutters. And if you happen to visit during off-hours (2200-0500 hours) you're likely to be the only one there and can take your time.
I say this not to shoot down the idea of keeping your stuff off-site. But if done cleverly, i.e. putting supplies secured and hidden out of immediate sight, yet easily accessible if needed then this is a viable option. I just wanted to raise it to attention as up until now I've taken my fair share of burglary reports at these places. And in all of these cases, the companies/employees could give less of a shit about addressing or resolving the issue of security.