Assuming living in a Tier-1 where the tech-hubs are (Beijing, Shanghai, Shenzhen), rents for a 2/3 bedroom apartment somewhat centralish (these are vastly larger, more populous, and higher density than most American or European cities) will be at least USD 2000, possibly 4000 depending on taste (apartment, not house). Pension may need to be privately paid, and tax-band will be above 40% for anything that can support the above. Purchasing equivalent consumables like food and eating out western-style will be the same or double than the cost in most of the USA. If with kids then international schools are pretty expensive in China, over USD 20k per kid per year. International driving license not hard but car questionable as the above Tier-1 cities have restrictions / waiting lists / lotteries on license plates.

Cost-of-living adjustment is only relevant if: no kids, no pension, able to adapt to eat locally (quite hard for a lot of people especially when hitting the ground with a full time job), don't mind a 30-60+ minute subway commute (cheaper rents).

Real Estate prices in the best areas of Beijing can easily top $1,000 a sq. foot to buy an apartment (though there may be an inversion in rent). Comparable cars are more expensive. Consumer goods are about par. Education for kids can be expensive.

Food can be cheaper in China. But a western quality life in a first tier city will not be all that cheap.