We were 7 days in Istanbul and over all the appartment was/is good! It is in the basement - from the entry on the street you go 2 levels downstairs - and therefore it is a little bit dark. But normaly you are on the way through Istanbul by day. Also it is not so hot and the absent aircondition is not missing.
The room is clean, comfortable and nice. We were a couple and the room is big enough; the bed is 120 cm wide, but we loved it :-) If you are not a "Michelin-decorated chef" the kitchen-corner is sufficient. The "garden" is ridiculous: a little grubby green with nothing but a few cats; but they are lovely. Also the bathroom is not the hit. But for a short shower it is ok. With a little effort Pinar can grade up the basement in these aspects significant.
The location of the basement is great! Near the touristic centre of Beyoglu and also away from it in a quarter where the more poor and simple people live; you get a feeling of the "real" Istanbul. The people there are very friendly and laid-back.
We don´t met Pinar because she was busy elsewhere. But she cared well in preparation of our coming. And her friend, Yakup, is a nice guy who maked it at best - thank you!
We would come again.