Could not recommend this place more. Fedon is an excellent host and offers plenty of really great suggestions for food, trips etc.
The apartment is homely, clean, COOL, and has a great balcony with a view of the art house cinema so you can have a sneak peak whilst drinking a beer.
The location of the apartment is hugely beneficial as it offers an alternative non-touristic experience of Athens whilst still being a stones throw away from the bustling city centre. The restaurants and bars in the area are authentic and hip, offering a much more romantic experience.
Check in and check out was super easy as well as transfers to and from the airport.