So you want to catch a thief? How about this for a sting - load up a couple of kite bags with some of those banged up old learner kites you havent touched in years (or a tarp or whatever) and drop a GPS transmitter in the bottom of the bag. Theres some kits here
www.byonics.com/products - obviously costs money, but could be fun on a no wind day - dont ya reckon? could even hit the jackpot, and recover some lost gear that never made it cash converters...[}:)]