That's why I never buy a car with built-in sat nav. I have a Garmin with lifetime updates for £80.
I bought a vent mount which keeps it all nice and tidy. You can also use the Garmin in any car, built-in you can't.
With regards to buying new with sat nav, I would have asked for at least first 2 services and nav updates whilst still under warranty. If they refuse, try another dealer.