Disc Lock for sure, maybe aftermarket alarm with a pager/text to your mobile, Tracker is actually not too expensive and 99% chance you would get your car back, security mark your car and removable bits. More likely that it would "towed/Trailered" away than broke into and stolen/keys from house, so make it unmoveable at your home. I think the Dreamscience is brilliant in that as well as tuning you car up you can add a "blank Map" and the car won't start so another good antitheft device too.