Just perfect! Clean, spacious apartment. 2 toilets, nice warm shower. Aircon was cool and nice to come back too after a day roaming the Bazaars. Location sat perfectly between Taksim square and the tram stop (down the hill) which is the main route to Besiktas and other touristy spots. Flat is well equipped, with a pharmacy, bakery and supermarket directly outside. Its only 1 floor up, not 2 as mentioned in one comment, and the street is close enough to be convenient but not too loud at night. Saturdays are an exception as it's the weekend and the whole area is buzzing - which is nice :) Great coffee spots directly outside too.
We were a family of 4 adults and found it very spacious. Sukret was super attentive with any requests and even waited up till 12am to check us in. Wifi worked perfectly. TV has Netflix / youtube capabilities also (not that you'll spend much time indoors anyway).
There's also a local cat which loiters outside the building and gets fed there, we were best friend in a matter of days.
We will stay here again next time we visit Istanbul for sure.