The accomondation has everything which you need to have a good stay. The Staff is really helpful ( special thanls goes to Ali). The communicatin with Güner and his crew was smooth and easy. The Area is fine but do not suggest something super luxury or whatever but if you need just a stay and no 5* Luxury Accomondation this one will be fine.
Taksim is about 10-15 minutes walk or two stops by bus.
Istiklal is reachable in 5-7 minutes by walk. Try Dürümzade the food is good and cheap and it is just two streets away.
Anyway i would recommend this appartment.