It was one of my best stay in Istanbul. Location is TOP! So close to posh civilization but so quiet in the night. Easy to get to. Building has an elevator (!) you'll appreciate it only if you were staying in that area before.
Check-in process is super-easy, Mert does it himself. Always on the phone for everything I need (I was asking for extra blanket for example). Apartment is light, nice and clean. I highly recommend it