If you look at the map of the covenant, you'll see that there is a nhmber of independent towers in front of the main coumpound. The covenant doesn't have a wall around it, so doesn't really have large enclosed courtyards.
The larger the space he has, the more flaws it will have. The covenant doesn't have enough mundanes to keep all its buildings in good repair, and is very unlikely to have them at any time in the future. And the peculiar nature of the aura means that unused spaces them to change over time, so anyplace that the covenfolk haven't used regularly tend to... evolve indepedently. So if you pick a whole tower, it is possible that parts of it won't have stairs leading up to them, or no wimdows, or plants/fungi growing in it. Any basement level is won't connect to the cave system -- there seems to be only one point of entry for those.