The host, Alen, was very nice; he met us at the apartment building in his office and after photographing our passports he showed us the apartment. The apartment is very nice and cosy, and clean. The building is quiet, and also has an elevator. The apartment has views of the street. The area is very nice, there are many small supermarkets in the neighborhood in short walking distance, there's actually one right across from the building. The apartment is also in walking distance from Taksim square.
We had a nice stay in Alen's apartment, and would recommend it to anyone visiting istanbul, who also wants to be in a central location with respect to touristy spots.