We had a great time at invictum residence. The room was very nice and clean. Only the insulation in the windows seems to be a bit weak. We were on the 2nd floor and it sounded like people outside would be standing right next to our window. Istanbul can be very noisy at night so that would be the only thing to improve. The reception is open 24/7 and the staff is very helpful. Location is in the heart of Istanbul only 3min walk to taksim square. Definitely worth staying.