Pros:
This is the best location! Less than 10 minutes walk from the bus shuttle from both airports. There is no need to take a taxi from there. Near the station of sea ferries and metro. From here it is easy to get to anywhere in the city.
There are a lot of restaurants around with prices much lower than in the city center. There are many clothing and cosmetics stores around. There are also several grocery stores around. The nearest one is 2 minutes walk
The apartment is well equipped. The kitchen and bathroom have all the appliances for a comfortable stay.
The interior doors are very thick, which gives good sound insulation inside the house. If one of your friends goes to bed earlier, others will not disturb him
The apartment has a smart lock. No need to carry a key with you and no need to match each other with friends, which usually happens when you have one set of keys for a large group
Wi-Fi is good. Allows you to comfortably work, make video calls and watch movies
The owner was always in touch. He explained everything in great detail about how to get to the apartment. And he answered all the questions
Minuses:
The hair dryer has very weak power and is practically useless.
The apartment is located on the 4th floor in a building without an elevator. You have to climb a steep narrow staircase. If you have a lot of luggage, it will be very difficult to get to the apartment
The windows of two rooms overlook a busy street with music and songs until the morning. But this is Kadıköy :) It is unlikely that you will find a completely quiet place here. In the third room and in the kitchen, windows overlook the courtyard. There is almost nothing to prevent a good rest. And even the sound of the mosque is almost inaudible at 6 in the morning))
We really liked the apartment. It was good choice for 4 persons