Overall lovely - do not be concerned by the exterior of building as it looks quite old and dark, once you get inside flat you will see it is clean, very well lit and beautifully finished and furnished.
Our only disappointment was that we were told check out time will be flexible - in fact our check in was earlier than it should be. However the day before checkout we were asked to leave at exactly 10:30, which is the normal check out time. Since they told us they were flexible when we arrived, we made plans around a late check out, only to have to change our plans at the last minute. This was not a huge problem for us thankfully, but we would have preferred if host told us that check out is not flexible, so that we could have planned accordingly.