All the reviews are right.
1. The place is just next to Darling Harbor, close to train stations.
2. Big supermarket like Coles is just 3 blocks away and opens till late night.
3. There were two doors to get into the apartment so I felt it was separated apartment.
4. Most important thing is, the hosts, Chen and Monica, were so lovely. Always helpful and kind to us.
Thank you for great stay in Sydney!