Hanging on to Your Stuff
One way to prevent theft of valuable items in storage is to place them in the farthest corner of the storage area and then pile mountains of useless clutter in front and on top of it. Putting some slightly useful items at the front of the pile and then having a bunch really worthless junk behind it will discourage all but the most diligent of thieves. They will draw the proper conclusion and abandon the search before they strike the true vein of value hidden way in back.
Keeping Things Hidden in Plain Sight
Presenting thieves with a multitude of exactly similar items is another way of keeping valuables safe. If every single box in storage has the same size and label on it, thieves will soon tire of looking through an endless supply of carefully packed boxes of baby clothes, for example. Hiding truly expensive items inside the boxes of baby clothes can be an effective strategy.
Offering a Gambit
Another concept is to reverse the idea of misdirection and put something physically but not emotionally valuable right up front and then back it up with a bunch of obvious junk. Many criminals will be happy to score and maybe take a quick look behind their new prize before driving away without really checking for the hidden items.
Making Them Pay for Their Purchases
Because of the spread of wireless technology and low voltage electronic devices, it is now possible to deploy security camera systems in the most unexpected of places at an incredibly cheap price. Be sure you have a trusted provider for your security camera system. In addition, many units can provide warnings directly to the owner about any break ins or potential theft.
Whatever you decide to do, make sure you take precautions to protect all your belongings in storage. Be mindful of what you store and how you store it.