An occupancy database is in electronic communication with a plurality of location-specific distributed computing entities to maintain real-time update occupancy data for various entities. As those entities relocate from one location to another (e.g., moving from one apartment to another), distributed computing entities associated with both the prior and new location of the entity transmit information to the occupancy database to reflect the changed location for the entity. The occupancy database also maintains communication data for the entities and/or locations associated with the entities, and the occupancy database may share that communication data with authorized mobile/user computing entities to enable communication between those authorized mobile/user computing entities and the particular entity or devices located at the entity's location.