Shortly: well equipped apartment rather close to the main (and noisy) street.
We stayed at the place for 1 week and were working for 5 days of these 7 days.
Pluses: Nurten was very polite and provided apartment with all we needed. Nice table in the "main" room to work on. Kitchen is fully equipped. Washing machine. The first floor (not high place to lift baggage) + windows view on the other street (rather quite one, no cars drove there) from 2nd-3rd floor because of the sharp height difference between streets. Close to Taksim metro station.
Minuses: the main minus for us was location. The apartment is 150m from the main street Istiklyal. So: (1) There was a night club which could be heard from apartment. I even woke up two times because of loud music while my wife was sleeping and haven't heard anything.
(2) there was rather active traffic on the street (normal for narrow streets near the main street).