We stayed in Orbays apartment for one week and it was really nice. The flat was very clean, the kitchen had everything we needed, the internet was fast and there were also enough bed sheets and towels for us. If necessary there is also a washing machine. Furthermore the public transport is easy to reach (Marmaray and Busses). The next stores are just 3 minutes away.
Next time I am in Istanbul, I'll check again if Orbays apartment is available!