Hayati's apartment is very nice and the location is good (near Taksim square and the metro station is close by as well as other public transport). It was relatively quiet and you could use the kitchen to cook or wash your clothes, which is very good. The warm water in the shower needed a little while to heat up, but all in all everything was fine and definitely recommendable if you want to stay a couple of days in Istanbul and discover the city!
Hayati was very flexible and helpful when we arrived later than planned and had to leave early. He also left us a guide booklet and gave us some tips and information about what we could do. In case of questions, he would always have been available. Hayati was a very good host and his apartment was equally nice :) Definitely recommendable!