Systems and methods are disclosed for maintaining security and data gathering for a number of vehicles. The systems include a vehicle activity module for each of the vehicles. The vehicle activity module has a wireless transmitter, a storage device, at least one sensor for receiving event information from identification devices, such as RFID cards, keypads, magnetic ID cards, and the like, a releasable key container, and a processor for accessing and analyzing information. The VAMs are wirelessly connected to a computer system. The VAMs control access to the keys, monitor information relating to access, and store and transmit information relating to sales events, non-sales events, and intrusion events. The VAMs are capable of autonomous operation, without the need to access the computer system to verify event information. The VAMs further include signal attenuating mechanisms to facilitate use of “smart keys.”