My stay at Eleni's place was absolutely perfect. The flat is lovely, very well designed and equipped with every convenience you might need. It is also very private and quiet with it's very own outside space.
Eleni's place is perfectly positioned for exploring central Athens on foot. I originally planned to stay in a different part of Athens, but was very glad to have ended up in Koukaki. The area is quiet and safe to walk around at night, with a wide choice of reasonably priced, good quality restaurants. If the evening is clear, don't forget to climb The Filopappou Hill (literally behind the house) to see the sunset.
Eleni is a lovely person and a very helpful host. I would gladly stay with her again. Very much recommended.