Are you looking for the ideal apartment entry systems for your apartment complex? Our Apartment Intercom Buyers Guide will walk you through the various factors to consider when selecting the right system for your building. An intercom system, at its most basic level, allows tenants of a building to interact with visitors and authorize entry to the premises. Visitors phone the apartment they wish to talk with using a front entry unit, and the renter can respond via an in-unit intercom and unlock the door by pressing a button.