Depending on their type of flight, access to a steep dropoff would likely be far more valuable than a flat area. Winds tend to flow up the sides of buttes like that, offering ready-made lift. A dropoff allows for getting airspeed by falling. So higher cliff-edge dwellings would be more valuable. Bridges connecting the two sides would likely have takeoff platforms or simply no railings to allow for quick flight.

Flat rooftop landings would likely be the most efficient means of entry, with ground-level entrances purely for trading purposes with the lesser races. Assuming the usual laziness of life-forms everywhere, there would likely be at least one elevator or lift system per butte to allow for moving heavier cargoes and people up to higher levels. Assuming some sort of racial claustrophobia, I would expect to see lots of external stairways connecting to bridges and jump-off points.

With magic, there might be lift towers (areas with permanent strong up-breezes) to let the people get to higher levels with less effort. Otherwise, a basic crane or powered rope loop (perhaps like a water-powered ski lift) would probably be present.