Overall a great place to stay. I and my mom spent 4 days in Athens in Argyro's place. The only thing by which I was surprised was the noise. The apartment is placed right by a schoolyard, so starting from 8 AM on weekdays the noise might be annoying. Also, the apartment's door is placed right by the entrance to the house and when someone enters the building - it's pretty loud too.
Other than that - this place was amazing.