Güngör's place was just what I was looking for. I spent here one night and it was absolutely perfect.
The Airbnb is just as described. You also have a great view of Istanbul and the sea :) I think it's perfectly functional for someone looking for a short stay in Istanbul. Everything was clean and the wifi worked perfectly well.
Güngör is a wonderful person. He offered me coffee and we had a lovely chat about his country.
I would recommend this place to everyone. Thank you again, Güngör!