Hakan’s place has everything needed for a comfortable and pleasant visit, and I would be happy to stay there again. The Yeldeğirmeni area itself is also interesting – every few weeks there seems to be a new café or restaurant or art gallery opening. As others have mentioned, the apartment does overlook the Marmaray railway line and the Ayrılık Çeşmesi station. I was there in the winter and wore earplugs, so the noise from the trains didn’t keep me awake. If you are a light sleeper or sensitive to noise, or in the summer with the windows open, you might find the trains a bit loud though. (The first train runs about 6am and the last one about midnight.) On the plus side, being so close to the station is great for travelling around the city!