We had the luck to stay at Cihan's place for almost a week. We just arrived to Istanbul from road trip and didn't arrange an accommodation in advance (our bad), so literally it was the last-minute call. Cihan replied as soon as we clicked 'Reserve' button and let us check-in immediately.
The room was immaculately clean and very spacious with a great view on the city and Prince's islands from the terrace. Communication was easy peasy as both Cihan and his father speak English fluently. They're very friendly and hospitable people, so I highly recommend that you choose their place to stay in!