Average hotel let down by the following problems:
Big problem: No noise proofing in the rooms. Between roughly midnight and 1am every night what I think was garbage collection was, very loudly, happening on the street my room was facing.
Medium problem: - Insanely hot in the corridors outside the rooms (inside the elevator was 24C, on days when the outside temp in Istanbul was ~ 12C). Even with my room temperature turned down it was still a bit too hot.
Small problem: Poor breakfast. There's cafes in the local area though.
Also, when I stayed (early April '19) there was no sign for the hotel outside the building. Best as I can tell this hotel, the Mood Design Suites, and one or two others are all part of the same building, with a shared reception. But of these hotels, Ayna is the only one without the hotel name visible from outside. So we walked up and down the street looking for the hotel before giving up, phoning reception, and being waved in to what we initially thought was the wrong hotel.
The room was comfortable, no problems with the staff, the wifi worked, etc. But given the choice, I wouldn't stay here again (or on any of the hotels on this street) because of the noise issue.