I stayed at Frankie's apartment for three weeks in January 2023. I must say this is one of the greatest Airbnb experiences I've ever had. The location is perfect; you can easily arrive at any corner of Sydney by bus or train. Many cafés, restaurants, and bars can be reached near the apartment. And Zetland is indeed a very quiet and safe district.
The room is as described, and it is pretty spotless. I successively shared the living space and bathroom with three different friends who stayed in the other room. Don't worry about the bathroom; it's shared by at most two guests including you, and our host, Frankie, will urge both guests to clean the room. Frankie must be a big Plus for staying here. He never bothers you, but if you need him, you can always expect his response (via Airbnb message) within one minute!
I would definitely recommend you to stay here, especially if you prefer a quiet and clean space.