We had a lovely stay with Giota and were well looked after. The private roof terrace with the pool really makes it and one of our favourite days was spent lounging up there in the sun. The location is very quiet despite a reasonably central location.
The shower is excellent as well, which always makes a big difference and it was nice to be greeted with a bottle of beer in the fridge. I needed it after pushing a very heavy suitcase up the hill - it does get quite steep and there is a fair bit of it which make this place unsuitable for anyone that has trouble walking.
That said, without a suitcase it's a short walk to and from the metro, making the place easy to access from the airport and a great leaping point to get around the city. Alternatively it's about a 35-40 minute walk into the centre of Athens.
Would recommend.