Julie's falt is very well located, close to lots of local shops and about 5 minutes to the heart of Istiklal street. You can find grocery shops which are open the whole night, but at the same time the neighbourhood is slilent to provide you a good sleep!
The communication went very well with Menekshe (Julie's assistant) and she was very helpful!
We stayed in the second floor and climbing the spiral stairs was still ok for my mother (65 years old)!
All in all, if you are looking for a reasonable place in Istanbul, you are on the right page!