We enjoyed very much our stay at Okan Bey appartment. The place has security guard which is very safe. It was also very clean and well located. Every location is very close: Taksim in 5 mins, Karakoy and Galataport in 20 mins, easy to find a taxi to go to Nisantasi, Besiktas.
Very much recommend this place and looking forward to stay next time, we will come to Istanbul.