I am going to test drive a Fiesta ST today. It is red with the Recaro package, moonroof, and painted wheels. They have it as the invoice price of $25,390. I have good credit and am hoping to do the 0% financing + 500 cash back, but I'm wondering how much wiggle room I'll have if we decide to take it home today. Can anyone give me ideas realistically of how much I might be able to talk them down?

EDIT: I live in-between Wichita and Salina Kansas. The dealer is in Salina.

Thanks in advance!