Unbeatable location right in the heart of Kadıköy but still quiet due to it being on the top floor away from the street. I didn't spend much time with Arda but he seems friendly enough. Although Arda and his brother both smoke, the bedroom is well ventilated when you open the window and this was not a major problem for me.
Re check-in, you should message the day before to confirm your arrival time, as the check-in time on the listing might not always be accurate.