Metin's apartment is extremely well located, only a few steps away from Ayasofya. It is perfect as a base for discovering the historic (and very touristic) neighborhood of Sultanahmet but it also offers good connections to trains and ferry boats. The apartment itself is nothing special, and it might become very noisy (there was a construction going on as we were there) but all in all is more than ok. Metin is really nice and helped us with everything we needed.