Positive sides: Nasri is a very nice host! He is super flexible with check-in time. Communication with him is easy and fast and he is responsive at times of need. He was very kind to make us a pot of tea with sweets upon our arrival. He also kindly organized for us a van to take us from the airport to his apartment(of course not free of charge). He also made us some sticker notes about places to eat and visit which was a very nice idea. Location of the place is very nice in terms of reaching historic places + public transport + shopping. Probably the strongest point which attracts people to his place is its location.
Negative sides: the place is not clean at all. Sofas/couches are dirty. Sink in the kitchen looks awful. WC needs cleaning as well. Shower room is a real disaster. Bad smell comes from the shower sewage and he put a piece of stone to prevent it + one of these automatic machines (Duftspender) which they spray fragrance every hour or so to compensate for it. Since it is a basement when other floors use water you constantly hear water running through the pipes. This gets annoying specially during the nights. There was also a bag of trash in the flat when we arrived which I think he forgot to take out. I and my family stayed for a single night and got out the next morning and to be honest if it wasn't that late when we arrived I wouldn't even spend the night there. Although we just spend a night there we were charged for 2 nights! Because of stupidity of airbnb staff on cancellation of the place. Finally Nasri called them and canceled the stay. All in all with the current condition of the place, I strongly advise families NOT to go there. It is not good at all for families. If you are a single person or maybe two friends or so you may wanna go there but still I won't advise to be honest. If it is your first time in Istanbul and you haven't visited Turkey before, I strongly discourage you to stay there. If you know already/or have a feeling with the average Turkish standard you may wanna try this(it is definitely better than a hostel in Istanbul but worse than a hostel in Munich).