HeY GuYs! Currently on my RoLLa, I got an aftermaket alarm sytem that uses the existing remote. The alarm is Mongoose. Model is MAP1100S. It cost about $400 I think. I got it at the time when i brought my RoLLa. The Toyota dealer actually recommended it over their geniune one. It is a pretty good alarm system. Here is some info on it: Many new vehicles today have factory remote controlled central locking and the last thing you want is another remote on the keyring. The MAP1100S is controlled from your cars' existing factory remote control. the MAP100S upgrades the vehicle's central locking to a full security system. The MAP1100S is very comprehensive and is equipped with an automatic engine immobiliser, full alarm functions, 2 stage impact sensor, black wiring, battery back-up siren, safety ignition door locking, automatic re-arm and automatic re-lock to name but a few. If your vehicle already has remote controlled central lockign,then install a MAP1100S - it was specifically designed for your vehicle. Or u can check out the website. Mongoose Alarms