Hi Dean
If a previous or another car in your ownership has/had Tracker, they will do a deal on the fitting cost for an additional car, but not on the annual licence cost. Give them a call.
I have a mixture of Tracker and Cobratrack between our little family fleet. It's becoming a pain that Cobratrack units will fail a monthly healthcheck 'ping' if they are kept in an underground bunker garage.
Also, try challenging your insurer - they seem to want them on everything nowadays. I had to put one on a MB A Class which seems a bit excessive