The cost of living for expatriates in Hong Kong as at 1 April 2018 is very high in comparison to other places in the world.

Hong Kong is for example 85.9% more expensive than Houston TX for groceries, 337.5% more expensive for household costs than Kuala Lumpur, and 52.1% more expensive for transport costs than Dubai.

The economy of Hong Kong is characterised by the principle of "one country, two systems", whereby Hong Kong runs on economic and political systems different from those of mainland China. Hong Kong is one of the world's leading international financial centres, with a major capitalist service economy characterized by low taxation, free trade and minimum government intervention under the ethos of positive non-interventionism.

https://www.xpatulator.com/cost-of-living-review/China-Hong-Kong_50.cfm