A:AnswerI got the viper ds4 and the gps cel module to be able to remote start from my phone. The gps module uses a yearly service that you have to pay to use.
A:AnswerI recommend the field disturbance sensor. It detects people walking near your car before anything is done, to show you have an alarm and to deter theft.
A:AnswerSome alarms come with the installation included. If not you could get the Geek squad total support for 200 and you could use it for the install costs for both cars. The total support lasts for a year.