You'll like it. It's a great tool.

Yes you could use your 8 free credits and license all 1998 Grand Prix and all 1999 Grand Prixs. If you want to license anything else you'll have to purchase credits. Because of how expensive additional credits are, I would charge others so you can essentially recoupe you wasting your credits on them.

Btw. The license is for editing only. You can scan any GM Ford Dodge, etc they support.