It's a 2003 330i ZHP, manufactured March of 2003. It has a nav system which I'm pretty sure hasn't been updated since then.

From looking around the forums a bit, I think I understand that there are two components that need to be updated:

1. The navigation system "software" itself.

2. The map, which is probably a $100+ DVD from BMW, which I refuse to pay.

Are those the only components I should be concerned with? If so, how do I go about updating the nav system software?