Hi, Yes it is pre-installed. We are on the 1st Floor and I think ours is ducted (but not absolutely certain) we just have the "grills" in the rooms (so whatever that type is, not very technically minded I'm afraid??)
The time to install sounds about right. We had problems getting the unit to the first floor as we had no access to the garage area (North Block) They had to haul a lot of "stuff" up by rope onto the balcony at the golf course and carry the unit all the way round!!
Remember the unit has to be at ground level on the balcony!!