for the FREE upgrade coupon (e.g. it'll show COUPON APPLIED to all cars from compact to intermediate, or Ford Focus to Dodge Avenger, and Ford Fusion)

this is 4 days at SFO

which one do we pick?
the Ford Focus ($134) and hope for FREE upgrade at pick-up from the coupon

or Ford Fusion ($154) and hope for $20 discount at pick-up from the coupon?

Thanks