I have stayed at Pinars house for a month. It os a clean, cosy house near taksim (+- 12-15 mins walking). There is a BIM and carrefour supermarket nearby and a few hundreds meter away there a lot of restaurants. Especially if you'll study at Bilgi University, the dolapdere campus is just 5 mins walking.
The only downside is that the neighbourhood is a bit ghettoish, but I did not experience any problems or whatsoever. But for just a girl, it may be unsafe to come home very late in the night.