We had a great stay at Nadia's place. Communication was very quick and easy and the apartment had everything we needed. The button water heater does not work for 6 hours as advertised, though. After 40 mins of heating, we had hot water for 10 mins tops, so be quick in the shower!
This bit is totally unrelated to the Airbnb itself, but for any fellow travelers visiting Athens: do not under any circumstances leave anything even remotely valuable in your car, no matter how long.