Nicole is a great host. She is very hospitable and ready to help during your stay. The apartment is placed in a really convenient neighborhood, you have several nice restaurants and cafes nearby and at the same time they are placed just at the right distance, so you don't hear how people spend time there at night (because sometimes night cafes in Istanbul are a problem), so you will have a good sleep.
It's easy to get to Istiklal, Taksim Square, and a beautiful embankment from this place. If you are a foreigner you can find a cinema with films in English on Istiklal.
Also not so far from the apartment you have Kabatas port in 15 min walking and if you gonna visit Prince Islands and really convenient to there from this port.
So I totally recommend staying in Nicole's apartment and I hope you will have a great time.
P.S.
And also she has an awesome couch with a TV, it's really comfortable to spend evenings on it and watch some series. You just need HDMI input on your laptop.