Tough to rate. So there are some pros and cons.
Pros:
Ayshe is super helpful and friendly, always ready to help with an advice or anything, she even was ready to bring us istanbulkarts. Her hospitability is the biggest good thing. We did not expect music to be so loud, but we managed to negotiate with Ayshe and reduced the length of our stay, and as always she was ready to talk, to discuss, to help and to look for a solution that is acceptable for everybody.
Istiklyal is just couple minutes of walk nearby.
Cons:
Music. There is a nightclub right below the apartment. And a jazz club or tavern of something. If you are reading this and other reviews and think "ok maybe it's not that disturbing" - oh, sweet summer child, it damn is. Music (good, admittedly - wish Russian night clubs had similar repertoire) is really loud sometimes up until 3 AM regardless of day of week.
And it's a bit humid but that's probably just a winter thing.
In general if you go to Beyoglu for night life and don't care about music - be sure to book. Ideal for a company of ~4 young people looking for clubs and fun who are not bothered by loud music.
If you are looking for calmer stay - better surf AirBnB some more.