I want to say Thanks A lot to greatest host Boutaina and her cat Oreo. He didn't let me get bored :)
Boutaina told me where to go in Istanbul and what to see. She showed me where the metro is and where to buy the SIM card.
And I want to tell a few words about room. It is a lovely bright room with a big bed. It is a balcony there, a teapot, rail for clothes, a desk, a chair, a mirror, towels and glasses.
I would definitely recommend this host! Thank you, Boutaina, now I know where to stay in Istanbul if I would return there.