Careful when using AA miles for a car rental! They only pay the car part of the rental!

As clearly(?) stated on the web site, when you get there you will need to pay all local/city/state/sales taxes and other fees (such as concession recovery fee, vehicle license fee, etc). Often (i.e. Las Vegas) those are more than the charge for the car itself!

p.s.
It can really be confusing using AA miles here (for hotels and car rentals) as when you do a hotel via AA miles they do pay the taxes but still don't pay some things like resort fees, etc.