I used to live in Kolonaki, so I already love the neighbourhood. Lots of nice coffe shops, views etc. But what sets Cleo's apartment aside is that it's on the top of a building with a giant area on the roof overlooking most of the city. It also stands out as being very quiet (Athens can be quite noisy, after all) as the place is situated in a dead-end street and is high up.
Also very clean and tidy. And I like that it has a laundry machine, so it's possible to wash clothes along the way. This becomes even more important in that hot Greek summer.
All in all a super experience staying here. Love waking up to the sun on the roof and having coffee while the city wakes up.