We stayed 3 nights and loved the flat! Very stylish and super clean. Apartment is on the top floor with a nice balcony. Didn’t really use it because we were out all day and the flat is located on a Main Street - but once the windows are closed, you don’t hear that anymore at all. :)
Location wise, there are many coffee places and cute restaurants close by, we really enjoyed the area. It’s in Excharia, which is known as the “anarchist” area of Athens - we did not feel unsafe at any point, however were asked a couple of times if we wanted to “buy something” close by. Other than that, everything is reachable quickly by foot or train. Definitely a recommendable place!