The apartment is even more than just good! We moved there last minute from another apartment in Istanbul and this one has all the advantages that the other one missed. They kindly approved our booking after 2 minutes I texted them.
1) It's very clean and they clean it every day
2) It's spacious and bright
3) it has everything you need (including towels and shampoos, hair drier, coffee, tea etc.)
4) the AC works perfectly, but probably you won't even need it, because the apartment is really warm (the reason we moved from the previous apt)
5) WiFi is also good, they have several routers, so you can connect to all of them and choose the one which is better (the reason we moved from the previous apt)
6) hot water in the shower
7) location is good, very close to the metro and Istiklyal
8) kitchen with everything you may need to cook
Several MINOR cons:
1) a little bit noisy
2) there a lot of trash in the street in that location
However, i would highly RECOMMEND this place to stay!