This is a rave review...
Location: in the heart of Kolonaki, the most desirable neighbourhood in central Athens. Within blocks of the apartment are food shops, smart boutiques and fun restaurants and bars, and a few of the city's top museums. A short walk or an inexpensive taxi ride away are Plaka, Psyrri and Monastiraki - the other areas of interest for visitors.
Apartment: immaculately clean - things like the back of drawers and under-sink cabinets were just spotless! The two bedrooms are generously sized, with large closets. The two full bathrooms (both not ensuite, and one much larger than the other) were, again, sparkling clean - both with good hot water pressure and nice amenities. The WIii was fast and stable and there is AC in every room. The bedrooms face the back and are super quiet. Even the front rooms are quiet (though the apartment is on one of the main streets in Kolonaki, it is not a through street, so even during the day the traffic is not really noticeable). There is only one apartment per floor, there are no immediate neighbours, you've complete privacy.
Management: The team at Upstreet is really at the top of their game. So professional - they anticipated every need and question a guest could have. Every message was answered promptly and warmly. And they could not have been more accommodating nor kinder.
I wouldn't hesitate staying here again, or in any property they manage.