Yaşar was very responsive, he could meet us much later than it was agreed. We were three adults and a child - it was totally OK. A bit cold at March but the conditioner worked well and saved us. Really close to Istiklal street, a lot of shops, cafeterias, ATMs, etc. Wifi was working normally all the time. Bus stop from/to airport is in 15 min to walk.
It was the 4th or 5th floor with very narrow stairs - really difficult to bring all the luggage upstairs. Very VERY noisy from the street, it was more or less OK on weekdays, but the night from Saturday to Sunday was just awful, dozens of people and cars, extremely loud music till the morning. I would say that photos are quite better than it was in real life.
Anyway we were glad to choose this flat and actulaay spent several good days in Istanbul.