The high price is due to the greediness of the home builder in HK. HK local person are very easily satisfied with owning a home, no matter how tiny it is and how uncomfortable it is.
I think the government get rich by selling the land and home builder got money by selling the apartments.
And it is the residents who pay high price to live in a uncomfortable tiny place.
I think after several more years, the advantage of HK will disappear due to its living condition. also the environment is so crowded, and people will begin to move out.