This was our first Airbnb experience and it was perfect!
Costa's place was in a great location! Everything was in walking distance and we felt very safe (two young female travelers). The apartment was clean and private and a great respite from a long day of sight-seeing. Costa was a wonderful host. He had great suggestions for food and activities and those were some of our favorite places!
My one tip is that if you are arriving from the airport, definitely take the trains. They are inexpensive and there is a station just steps from the apartment. We were arriving in Athens at night, so we took a taxi trying to be safe, but Athens is very safe. We never felt in danger during our stay. I highly recommend going and staying at Costa's!