I definitely recommend this place! The apartment is close to Taksim square, so you are a few minutes away from Metro, Train, and Bus stops. The kitchen has pretty much everything you might need, but it is really tiny so you will be able to prepare only basic dishes, but there are plenty of restaurants nearby, and you can always order food, the prices are really low!
The place is very cozy, and I really liked the fact that the bed was so high up, you can see the whole apartment from it. The bed is also very comfortable, perfect for resting after walking in the Instabul for the whole day :D.
Emre was very helpful with tips regarding how to get to the apartment, and the desk of the Ottopera Otel (where you get the key and where you check-out) has very nice people.