Good communication with the owner. There is a reception which is open 24/7 and where you can go with your needs. The apartment near the shopping street in Taksim. You can get breakfast at the cafe next door. The cafe is small, cute and cozy. Here you can also use the WiFi during breakfast to check your e-mails.
Note, this is a basement apartment and there are no windows. It is very quiet, but also takes some getting used to and is not suitable for everyone. Overall it was a good stay.