We loved our stay at Konstantinos's apartment! The apartment is extremely comfortable and spacious, with all the amenities that you could need and Konstantinos even had a welcome bottle of white wine for us to enjoy. The location is perfect, right near the heart of downtown in Psirri, down a cool street filled with restaurants and only a few minutes walk from the Monastiraki metro stop. You also get a view of the Parthenon from the balcony and right across the street is one of the oldest cathedrals in Athens which is definitely worth checking out. Definitely would recommend staying at this apartment if you're visiting Athens.