Since this is being installed for you centrally by the managing agents, you are going to have to establish what equipment they are installing.
Therre is some general info to help you here at this BBC website.
http://www.bbc.co.uk/reception/digitaltv/index .shtml
However: -
1) There is no such thing as a digital aerial. The aerials that pick up terrestrial broadcasts are just wideband aerials - a very old one might not work since they were channel specific.
2) Sky can be received through satellite, cable or broadband.
3) It is also possible to get free-to-air satellite TV (in other words, the same channels as are found on freeview) using a satellite dish. It doesn't need a Sky box. It is my guess that that is what the managing agents are having fitted by Sky in your flats. Those that want the full Sky packages then couple it to a Sky box - those like you that don't want Sky can still get the channels.