We had a wonderful time in Konstantiono's apartment. The apartment is in a great location (Gazi), good bars are in short distance.
We cannot confirm at all that these clubs are noisy. We slept very well. But when you're in a city like Madrid, Athens, Paris, London, Cologne or Berlin, it can get louder. That's just how cities are.
There are good restaurants near by, as well as good gay bars (shamone).
The metro station Kerameikos is right around the corner, from which you can go all over with a 90-minute ticket for 1.20 euros. (Acropolis / Monastiraki / Psiri)
The communication with Konstantionos was super polite and very friendly. Thank you! We will definitely come back to Athen again!