Avis takes up to 25% off nationwide car rentals via coupon code "S9516001". (Select "I have a Discount Code" and enter this coupon in the "AWD Number" space.) That's the best percent-off coupon code we've seen from Avis since last summer when we saw up to 35% off. It's valid at participating locations only. Fees, insurance, and taxes are additional. Discount is reflected in the listed price.
https://www.avis.com/car-rental/avisHome/home.ac

Enjoy!!