Vassilis and Rallou were great hosts and their house is in the perfect location for exploring Athens. The house itself is spacious and clean, and the pictures are very accurate. They also have a folder full of recommendations all over town, and we enjoyed every place we were able to get to.
And the location is perfect in my opinion. The house is on a quiet side street just around the corner from the pedestrian walkway that circles the Acropolis. From the house you are a 2 minute walk from a metro stop, cafes, restaurants, night life, and even the Acropolis Museum or Plaka district are a very pleasant and easy 20 minute walk. It is a great home base for exploring the famous sights as well as the other neighborhoods and districts.
Also, if they are able to arrange a car for your to/from the airport or Piraeus, you should definitely take them up on the offer. The driver is extremely friendly and enthusiastic, and will drop you off right at the front door. He even took us for a quick trip around the block to point out some nearby restaurants and bars.
Overall we had a wonderful experience and I would definitely recommend Vassilis and Rallou as hosts.