The apartment is located on a sketchy-looking street but thankfully we never had any issues. It very close to the main pedestrian street with shops and restaurants, and Taksim square is just a 10 minute walk away. The kitchen is well equipped and the apartment was nice and clean, as on pictures.
Sometimes it was noisy due to traffic and thin walls, as well as the Sunday market. We encountered problems with hot water but managed to fix it ourselves. The insulation of windows and doors it not too good, there was a permanent draft and was quite cold despite having the heating on (we stayed there in March).
However the check-in management part we are hardly satisfied - one of us booked an earlier flight just to arrive in time for check-in and then arrived to meet the host at precisely 7pm (heavy traffic in the city), but by the time the paperwork was done it was 7:07 and we had to pay 20 EUR extra because of this - a little flexibility would not hurt and would have left us satisfied.