Kerem’s place was located near Taksim, very central and only a 5-7 minute walk from the Metro. It was really clean and the towels were replaced along with trash being thrown out every day. When we arrived in Istanbul we followed Google maps to find his place after we got off the airport bus at Taksim. It took us about 15 minutes but if you cross Taksim square instead, it should take only 5 min or so. The area can be a bit noisy at night due to many places being open very late and no one really sleeps.