I'll be renting at LAX in March for 7 days - Wednesday to Wednesday. I'd like a coupe (not convertible) of some sort - Camaro/Mustang etc. What's the best value way to go about this as a 5* member?

1. Standard D2 SSAR booking is around $350 which I assume would guarantee me a Mustang or similar?
2. Standard D SCAR booking gets me a Jetta or similar for around half the cost but of course gives me access to Ultimate Choice.

Not to come across as a cheapskate (but I guess I am), do I take my chances with the D SCAR booking and try my luck in the UC isles? What are the chances of coming across a coupe in the 5* section?

Can I grab something in PC isles and pay the difference?

Could someone also explain how the paid upgrade system works as a 5* member?

Any advice appreciated.

Thanks