I'd like to say that this apartment is a perfect choice if you'd like to spend some nice time in Istanbul and enjoy your stay.
First of all, the location is good, 5-7 minutes or so walking to the tram station, lots of nice cafes to have breakfast or to have dinner nearby and many shops around.
Secondly, the apartment itself is VERY good! The same as on the photos, big, modern, clean and beautiful! It has everything you may need: from kitchen utensils to washing machine (which is very important, especially if you have a long trip). The bed is super comfy, the bathroom is big, all in all, we were feeling really comfy staying there.
Last but not the least, we were welcomed to the apartment by Arek himself. We had a very late flight (and it was delayed as well) and still Arek has been waiting for us until we've arrived to the apartment. We really appreciated that.
Finally, if we go to Istanbul again, we'll definitely chose this apartment once again and we'll recommend it to our friends / relatives for sure. Thanks a lot and good luck!!