Me and my boyfriend stayed at this place for 1,5 week and we are very happy with our stay. The apartment is located centrally in Şişli and there’s restaurants, cafe’s and grocery stores nearby (just go down the street and to the right and you’ll find a big grocery store nearby). We found it easier to find the apartment with taxi if we told the driver to put in “Pizza Hut Bomonti” on the GPS, and the apartment is just around the corner and up the street). There is also metro very close to the apartment just a few minutes walk.
The communication with Aksel that was our host was also very helpful and he always answered very fast if I had any concerns or questions.
The apartment also has everything you need in the kitchen and we did not have problems with the hot water as other people has mentioned before. As mentioned, we were very happy with our stay and I can recommend to book this apartment if you want something central in Istanbul :)