It is all about location in Hong Kong. Mary's apartment is like less than 10 seconds away from one of the metro station exit, what more can one ask for?
Just like many other apartments in Hong Kong, it is hard to swing a cat in the bedrooms, you can try to do that in the living room though :)
Many thanks to Jenny for her patience and quick response. Definitely will recommend Mary's place for a group of friends or family who wishes to explore Hong Kong!