The stay at the Ilhan apt was great. It is nicely located at 15-20 minutes walk from Taksim, and less from the begining of commercial and busy pedestrian street Istiklal. Depending on your interests you may want to stay closer to Taksim (for me was fine since I needed also to move to other parts of the city). It is at 40 / 50 min walking to the Grand Bazar. The flat is like new, the bed is comfortable and the kitchen is ok (maybe a little small if you want to prepare complex dishes). Ilhan was very responsive to my questions and I am very thankful for his help in resolving an issue with the wifi the first day.