And amusingly, those fob systems increase the chance of a break-in to your apartment. In a building of 200-400 suites it'd be tedious to try found/stolen keys i

And amusingly, those fob systems increase the chance of a break-in to your apartment. In a building of 200-400 suites it'd be tedious to try found/stolen keys in every door. But in a system such as you describe you get on the elevator, wave the fob at the sensor, and press all the buttons. It'll only take you to the specific floor your stolen key will work on - narrowing the search time down to mere minutes.