Are there many types of trackers, please? 
Two from CobraTrak
About Cobra Trak First
The Cobra Trak First is a 24 hour monitored stolen vehicle tracker which means that should your vehicle be moved without your ignition key, the system will alert Cobra's 24 hour control centre who will call you to confirm that your vehicle has been stolen and, once you have obtained a crime reference number from the police, they will liaise with the police, giving them details of your vehicle's precise location.
Cobra Trak First uses the latest GPRS/GSM Technology and offers amazing network coverage ensuring that your vehicle is never out of range.
The system offers the following:
European Cover
Motion Sensor
Tamper Alerts
24 Hour Control Room
Regular System Health checks
Cobra Trak First Mobile
With Cobra Trak First Mobile you can confirm that your vehicle is still where you left it wherever you are and whenever you want to.
The Cobra Trak First Mobile is the same unit as the Trak First but the subscription is different. The yearly subscription charge is £169.00 with no option for 'duration of ownership'.
A link on your phone browser would give you access to your vehicle's current location in a map format as well as access to your tracking status which would allow you to set or cancel garage and transport modes on your system.
The subscription is £169.00 per year (incl. VAT) and there are no further ongoing charges.