What makes an observatory building special?
The most obvious feature is the roof. You need some manner in which to allow the roof to open to allow the telescope to see the sky. Some folks attack this problem with a roll off contraption of their own design, which I contemplated, but I never saw a fully remotely operable solution that I would trust (the roof needs to be watertight lest your optics and electronics get ruined), although there are some good examples.
