This is a luxurious feeling apartment in a great part of Istanbul. Many public transit connections are easily walkable from the apartment. The main level has a comfortable sofa, full kitchen, and a toilet. The lower level has two bedrooms each with a private shower and toilet, and a clothes washer and dryer. The top level has a desk with office chair which has nice views of the Bosphorus. It was winter when we visited so I did not spend much time on the terrace, but I did spend several hours sitting at the desk watching ships pass by. Internet was decent at 22.7 Mbps DN 5.62 Mbps UP with 155ms Ping though my VPN back to the USA.
The elevator drops you at the middle level so you will need to use the narrow stairs to access the bedrooms and the terrace, if you have mobility issues this might not be the place for you. The restaurant downstairs can get lively at night so you will noice it in the evening. This did not bother us, but know it will not be completely quiet in the evening.
I would definitely stay here again if I was coming back to Istanbul. It was great for two of us, but if you are traveling with a friend or another couple you would each have a private bedroom and bathroom. The experience with the host from pick-up, check-in, and return to the airport was also good. I would not hesitate to rent from them again.