That's pretty interesting, and seems like an "obvious" use for drones.

I bought a flat in Helsinki last year, and the online marketing included all the stuff you'd expect - location, details of sauna, rates, floor-plan, etc - as well as a video (hosted on youtube) which was obviously taken by a drone flying around the interior.

Had it been a freestanding house, instead of a flat, I'm sure the drone would have shown the exterior in a useful way too.