I travel to Athens a few times a year and this is by far the best place I have stayed in so far. Thisseo is a great neighborhood and very central. You can walk to all of central Athens within minutes and in the immediate neighborhood there are a ton of great restaurants and cafe's. The apartment itself is clean and spacious and you essentially have a whole building to yourself which is very rare in Athens Airbnb's.
The kitchen has all the important amenities and the beds are the very comfortable. We travel with a 4 year old and he loved the space as well! We will be coming back to this place next time we visit Athens.