Even though the apartment is not modern we loved Gülsev's place. Area nearby is great - there is a park close by and Bosphorus for you to walk. Public transport is also easy to use, no metro near, but buses are quite comfortable and go to all the tourist places.
There was a problem with hot water the day we arrived, but it was quickly fixed. Then everything was great! We even decided to prolong our stay.
There is everything you might need in the aparment - washer, hair dryer, cooking utensils. And Gülsev is really helpful.
I'd definitely recomend this place.