Cuneyt is a very nice host and answer very quick and are helpfull.
It's a nice, clean basic apartment on 3rd floor, located in Tophane in the middle of the nice areas Karaköy, Cihangir and Istiklal (tourist street around Taksim/Sishane), close to tramway station Tophane. If you want to hang around a lot in Cihangir and up on Istiklal you need to walk very uphill, just so you know.
The area around the apartment have some quite nice designer shops and cafe's.
If you have a child in age between 1-3 (which we have) the apartment is not optical because the windows are sitting low and if you need to have the windows open (which you need because of the heat during summer) you need to have an eye on the child all the time. Also the street where the apartment is located is on a staircase (not reachable by car) so you need to cary up the stroller.
I recommend the apartment because is was affordable.