Overall we had a great stay. Efthimis was very responsive and offered tons of great local tips. The apartment was clean, spacious, and had everything we needed, and was walking distance to everything we wanted to see and do in Athens. The apartment also has a spectacular view of the acropolis, especially at night, and we enjoyed sitting on the balcony with food and drinks in the evening.
We had one minor issue that could have been a major issue for someone less lucky. When we were leaving at 05:30 the outside door of the building was locked and required a key to get out...we were locked in! Fortunately a neighbor woke up and was kind enough to let us out, but had he not we would have been in danger of missing our ferry.
The apartment was located on a street that was quiet during the day but seemed to get a lot of motor bike traffic at night. It was fine on Thursday and Friday nights but kept us up a bit on Saturday night.