We absolutely loved Sakis' place!
It is very very centrally located and within 5 minutes from the Monastiraki metro station. There are good restaurants along Kokolotroni street as well as on Ailou street just down the street.
The apartment itself has quite a character, a mix of vintage and industrial design. It has everything we needed, including coffee :).
Check out, check in was quite smooth and communication with Sakis was great.
We would definitely love to go back and stay at Sakis again the next time we are in Athens!