Good value for money, but lower quality than in the pictures. In fact, our flat was a bit different than in the pictures (last floor apartment with significantly lower ceiling). I would also suggest the host to put emphasis on small details like cleaner windows, get rid of the wire that comes out from the wall in the bathroom, fix towel hanger and the window in the living room that is closed with the tape, clean sofas from spots. All these small details which are quite easy fixes made significant downside effect on our stay. And of course, the internet. It must be fixed, as you can't browse for 5 minutes straight without disruptions.
The rest was pretty cool, nice coffee shop on the first floor and very convenient location with good reach to pretty much everything. We had amazing time in Istanbul.