Fantastic location, two minutes from the green hill of Filopappou with splendid view, a few minutes walk from the Akropolis and its museum, the centre of Athens, great cafés, bakerys and restaurants in the area, neoclassical mansions - possibly the best neighbourhood of the city.
The apartment itself was clean, very quiet, cozy, with all the necessary amenities. The little yard outside is phantastic for drinking coffee, reading a book or even taking a meal, if weather permits. Gas heating means you can have a nice steady temperature and also warm water whenever you need, which is by no means a given in Athens.
Only minor disadvantages: the very small bathtub (there is no extra shower), which I personally didn't mind, but a large person might have a problem with; and the apartment is fairly dark, beeing on the ground floor. Especially in the kitchen one has to turn on the electric lights even during the day.