i have 3-4 tricks that may work or help you out.. 1..pushbutton start button that is wired to your ignition so you have to hit it to start the car.. 2..companies that have battery cutoff switches that you could hide... 3...take loose your battery cable and put the black cap the negative one most hidden back on the terminal and reconnect the battery they will not have a clue whats wrong 4.. have an airhorn like a trainhorn ran to an alarm everyone seems to ignore all the alarms out there its impossible to ignore this one... 5..pop your hood and pull the sparkplug boots loose from the motor takes about 20 seconds and leave them just resting on the sparkplugs but not attatched the motor will turn over but no spark.. 6..get an aftermarket steeringwheel with a disconnect on it and take the steeringwheel with you7.. my friend rests a huge screw under the 2 front tires so if his car gets taken his tires blow and cant be driven make sure you remove the screwbefore you drive... 7.. pull a main fuse like the fuelpump ect ... then just put it back in when you start the car just some things i came up with