Their variations depend on where they were deployed and the climate of that area.
In the G-A, they have been used to house soldiers, create synths and build vehicles. They also are used as headquarters for Gravitarian leaders.
They are also capable of sending broadcasts throughout the entire city, and can interrupt any other broadcast due to really strong signals.
Each room can hold 3 people. They resemble hotel rooms and come with free food and service as long as you are in the military, as a General or a Soldier. Elites get more services and even get to live with different gendered soldiers. (Eheh.)
They also come with 3 beds and 3 chests, each one for each soldier living in a room.