I stayed here for 6 nights and it was a terrible experience. The flat reeked of mildew, which seemed to come from the bathroom (it was worst there.) The washer and the fridge were not working. The kitchen was not clean. There is a two burner electric stove that was filthy. Only one burner definitely works. There is no hot water in the bathroom or kitchen sinks. The place in in disrepair and needs paint badly. I would probably have tried to arrange new accommodations but it was New Years weekend and things were booked up. I also had a work deadline and couldn't afford the time to deal with a move.
The only positives are the neighborhood, and Murat was pleasant to me in our interactions. Also, when a fuse blew the last night I was there, he fixed it quickly. But he kept telling me that he was going to fix things in the coming weeks or months, and that doesn't help me or the person staying right after me. The night before I left the only thing that worked well - the water heater for the shower - started leaking badly. It was on the wall, and the water splashing from it to the tile floor woke me at 4 am. Since I was up so early, I changed my train to leave earlier. Honestly, I couldn't wait to get out. My clothes stunk of mildew when I got back home (I am living in Turkey this year).
Reflecting on this experience, I do not understand the positive reviews. Maybe people are charmed with the neighborhood, which is lovely, or buy Murat's story that this is traditional Istanbul flat. Maybe things have deteriorated more recently. But I have stayed in at least three other AirBnB flats in this neighborhood (Cihangir) and there was hot water in the sinks. The amenities worked. They were clean. If you consider staying here, I would contact the owner and make sure the necessary repairs have been made.