Absolutely lovely place to stay.
We arrived in evening and were met by Georgia's husband. Had very good communication with Georgia as well though and she was a very helpful host.
The apartment is on 3rd floor with stair access and is in a very convenient location, very near a metro station. We only used it from and to the airport though as we walked to the places we wanted to see - eg Acropolis was only a 15 minute walk away!
We was me, husband and teenage son. The apartment is very open plan, yet still afforded privacy - eg son was in bedroom space off living area, but it is positioned so you can't really see it from seating area.
Would thoroughly recommend it as a place to stay in Athens. You will be in a lively area with shops, bars, restaurants, market and close walking distance to many places to visit. And your accommodation will be a calm, spacious, clean and comfortable place. We were really glad to have chosen it!