PROS: Fatma's place was very centrally located in beyoglu, lots of great places for food nearby. It's a quick walk to Taksim sq for the shuttles to and from the airports, and a couple minutes walk to the main street istiklal cadessi where theres all the shopping, cafes, bars, etc. Also very close walk to galata tower & bridge, and karakoy. The tram to the sultanahmet historical area (where all the major tourist attractions are) is just a 10-15 minute walk down the hill. The ferries to Prince's Islands from Kabatas also just a 20 min walk down the hill. All in all, EXCELLENT LOCATION!
CONS: 1) The STAIRS to the apartment are killer. The apartment itself is on the 5th floor, so say at night you had just walked up the hill from the pier or karakoy, then you still have to march up 5 flights of steep stairs. It's not a joke. 2) The apartment gets very hot - we went in June, there was a fan that we used, but it wasn't super helpful. 3) There is a mosque very nearby, so when they make the calls to prayer in the middle of the night (2 hours before dawn; and at dawn) you will likely get woken up - it almost feels like the microphone speaker is pointed directly at the bedroom window, it's quite loud. If you're a light sleeper, be aware of this, and maybe pack some heavy duty earplugs.