We felt very comfortable at this appartment. Panagiotis made small (but important details) to make sure we had a pleasant stay: waited us for a late check-in, left us fruits, coffee, soap, and even aloe vera (which you will need!).
The place is very well located. Right in front of a Corner with 4 bars: one fancy for drinks, the other for traditional food, a cooperative and regular one. This might make the place a little noisy at night; we didn't even feel it but we were left ear plugs in case we did. Also, it's close to Acropolis, Plaka, Subway (to the airport and Pireus) other restaurants and shopping district.
Communication was fluid and very precise.
It is definitely where I would stay in Athens once I came back.