We stayed at Sersah's apartment for 1 month and loved it. The apartment is a beautiful space and the area surrounding it is so full of life and culture. I've never seen so many cafes, bars and restaurants in one area. Great coffee, cool bars and great food are all within steps in literally any direction. You will go to the tourist areas once or twice, but you will never get tired of exploring Kadikoy. You are in the heart of the neighborhood so noise is definitely present, but the energy is inspiring more than it is bothersome and shouldn't deter you unless you are very sensitive to those things.
Sersah himself was an excellent host. He showed us nothing but warmth and hospitality from check-in when he met us late and took us to a great late night spot to have dinner. Even mailed us an item we forgot in the apartment after check out.
Overall great experience. Beautiful apartment. Great host.