I stayed here for two months. The location is great, about 6-7 min. walk to the Ambelokipoi metro station. And it is one street parallel and behind busy Alexandras Ave., but the apartment is surprisingly quiet at night. There is a good farmer's market every Tuesday on the street right in front of the building. The apartment is located on the rooftop, so you take an elevator up five floors and then walk up one flight of stairs. It has good light and a view of the mountains behind Athens.
The house was recently renovated so everything is basically new. The size is good for one person or a couple. A small living room with sofa/bed and table for two people, and an attached small bedroom with TV and closet. When I arrived the internet had not yet been installed (I used a portable device for a few weeks), but now there is regular WiFi (about 8MB/sec). There is an AC in the living room. The weather was getting cold while I was in Athens, so I used this to heat up the house. The kitchen is small but adequate for moderate amounts of cooking. It is a bit basic and a few more things should be supplied, like a frying pan, coffee maker, cutting board, etc. The bathroom is very nice and clean. A huge balcony at the back can be enjoyed during the evenings when the weather is nice, and the washing machine is here as well. Plenty of room to hang up laundry for drying.
The hosts, Maria and Loukas, were extremely friendly, and helped immediately with a few minor issues that arose. For example, the radiators needed cleaning, so in the meantime they brought over a portable space heater.