Ariz. Rev. Stat. § 28-4840
A. A vehicle that is left in a repair facility operated for commercial purposes for more than ten days after notice to pick up the vehicle has been mailed to the owner by certified restricted mail to be delivered to the addressee only, return receipt requested, at the address listed on the vehicle registration is deemed an abandoned vehicle. Unless the vehicle is left under a written or oral contract for repair, the party in possession of such a vehicle shall: