So I'm going to rent a car from Avis YYZ for 3 days Aug 4-7. I'm booking a compact using Aeroplan points. As I'm on holiday and recently turned the golden car rental age of 25, I'm hoping to upgrade to something fun to drive for the few days I have the car.

What does Avis YYZ carry in the way of Premium cars? I definitely don't want a Grand Marquis or Town Car, but I'd love to get something like a G8 GT, Lincoln MKZ, or one of the Caddys though I understand they set them aside as "specialty" cars.

What's the going rate for an upgrade? I obviously don't expect it for free but I'm wondering how much. I know from experience that Thrifty Bluechips generally pay around $15-20/day to get into a Premium car or SUV from a compact.

Any advice is helpful, thanks!