The apartment looks exactly like the pictures. Very clean and new. View is great. We did not meet the host but she is prompt in her email reply. We asked for more toilet paper and to replace the remote control batteries and she replied almost instantly and get the handy man, Mr Mustapha to come within an hour. There is a lift to the apartment and the lift looks new and cool too. The location is in a nice and hip neighbourhood with a lot of restaurants and very near to the main walking street. The Tunel is only a few steps away and we can go down to Old town using that (we can get the istanbul card from there too, you cannot get the card from the Metro, you have to get it from Tunel) , transiting to the tram at Karakoy.
Negatives of the apartment : the drainage at the bathroom is not very good so it may get a little overflowing while showering, but it's no big deal. Another point to note is that there is a flight of stairs down from the road before you reach the apartment, so if you have a lot of heavy luggage, you have to make sure the cab drop you not at the main road but at the side road which is next to the apartment entrance. We took a private transfer to and fro the apartment as we do not want to have to deal with the taxi driver. It is 25 Eur for private transfer to the apartment and they will usually help with the luggage as well.
All in all, GREAT place to stay, highly recommend for anyone!