We visited Athens in May and loved our stay! The check in was super flexible and George is very kind and a superb host. Based on the descriptions of the flat here on Airbnb George and Panagiota are honestly selling themselves short, there are so many thoughtful touches in the flat that are not listed, such as toys for children, a sewing kit, first aid kit, hair dryer and hair straightener, little bathroom essentials like deodorant, conditioner and tooth paste, umbrellas, slippers and so much more that is not mentioned in the description but just helps to make you feel welcome and well taken care of.
The apartment is right next to the station, which is super convenient. However, it is also right next to a busy street and the neighbours seem to have a newborn that fussed a little around 3am, but we had earplugs and they worked a treat, so keep in mind to take some with you if you're a light sleeper. Overall it was an amazing stay and we can thoroughly recommend it to everyone :)