I used to work at Best Buy as an installer. They carry the following Viper models
160xv: keyless entry, remote start, no security features
350hv: keyless entry, no remote start, security features
571xv: keyless entry, remote start, no security features, 2 way remote
771xv: keyless entry, remote start, security features, 2 way remote (1 on my truck)
971xv: keyless entry, remote start, security features, 2 way LCD remote
For more info go to www.directed.com
. The MSRP is usually Best Buy's price installed (or a little cheaper). I must warn you that the installation is going to be very basic. You have to pay for other features such as dome light supervision, window relay, prox. sensor, etc.
(EDIT: I realize now that this is for your girl's car. I am going to leave the rest just because.)
Also, if you have a 98+ you will need a separate module for remote start. We have a chipped key which emits a particular frequency when placed in the ignition. There are several to choose from, but I would recommend the DEI 556SW ($80ish). You will not have to give up your spare key with this unit. Unfortunately, BB will probably have to order it which will take a week.
Hopefully this helps and you can sift through my rambling. IM me if you have any more questions and I'll answer them the best I can.