New Gs300 Owner, Couple Quick Questions

[Ken300]

Just picked up a 2006, GS300 AWD with Navigation.

I'm guessing I have an old Nav Map DVD because it couldn't recognize a street

in a housing development that's about 9 years old!!

1) What Gen (generation) of map DVD do I need to be looking for. Don't want to

get a map DVD (probably used) and have it not work.

2) Is it possible/costly to upgrade from one's current version/generation of Nav system

to something newer?

Thanks

Ken