We had a nice stay in Giannis's flat. Giannis is available at any time to answer your questions, fix your issues, order taxi or anything you need.
The flat is in a popular area and quite central to visit Athens, less than 10 minutes walk to the metro or restaurants near the Acropole.
The flat itself is nice, clean, quite new and clear. The weak point is that there is no balcony and all windows overlook a courtyard. Nevertheless we recommended it for the price quality ratio.