Okan and his place are excellent. The host is extremely friendly and helpful, and the apartment is spacious and beautiful. The value is great as well. The location of the apartment depends on you and what you want to do in Istanbul, for me it was perfect. If you are a tourist and want to go around I recommend hiring a car, but public transport is great as well, 15 minutes walk to the tram station and 10 minutes walk to a major bus station that takes you to other cities etc. I highly recommend staying in this place.