A system for controlling access to equipment. The system establishes that a user of a mobile device has authorization to access an equipment and generates an encrypted digital key. The system sends the encrypted digital key to the mobile device. The system also sends an encrypted corresponding digital key to a controlling unit of the equipment. When a distance between the mobile device and the controlling unit is within a threshold, and the encrypted digital key transmitted by the mobile device is authenticated by the encrypted corresponding key on the controlling unit, the controlling unit unlocks the equipment so that the user of the mobile device takes control of the equipment in accordance with terms and conditions as set forth in a contract for operating the equipment between the user and an owner of the system.