Great location, very close (less than 10 min walk) to Taksim, also very close to nice cafes and restaurants on the lanes nearby. I dealt with Pelin's partner, he was very nice and the check-in experience was great. Also they stored our bags on the day of the check-out for a few ours which was a great help to us.
The flat was good, it was very clean, the sheets were all very clean and so was the bathroom. Generally the flat is very small and as someone else mentioned is it a bit damp but it's an old building so I don't think there's much that can be done about that. We left the windows open and that helped. It is a bit dark, but we didn't mind it as we were out most of the day. My only complain is that the bed was in fact a sofa bed and I didn't find it very comfortable. But still great value for money.