Simply rewire the car with RFID locks and get people this.

Or implant the RFID chip in the hands of all your friends. And when they're no longer your friends, well, that's one less hand they'll have.
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FireFox31
110gig MKIIa (30+80), Eutronix lights, 32 meg stacked RAM, Filener orange gel lens, Greenlights Lit Buttons green set