> There's really no reason why London/SF couldn't do that apart from government policy. I live in London and like it but wonder if having all the property being some silly multiple of wages is the best way to do things.
But Guangzhou has a much higher property price to income ratio than either London or SF. So, the policy you suggest doesn't fix the problem you raise.
But the higher prices in Guangzhou could be due to a much higher "maximal use" value from allowing denser development. If the property is 2x as expensive but holds 6x as many units (30 story tower in article vs typical 5 story American midrise), then that's a win. That type of cookie cutter high rise is very common in many Chinese cities. They will plop down several of these towers in the same area, typically 10+ stories, with few burdensome restrictions on parking and elevators. Can't speak to London, but I was blown away when visiting SF just how little dense development there was in most of the city, and how little new construction there was even of midrise buildings.
I believe it is per unit price not the whole building. It would be like family with 30 grand/year going for million dollar home. In China's case if would be an apartment accommodating 3-4 whereas in US it would be a large home in 99% of areas which are at max 20 miles from a city.
I lived in city of Mumbai, India where median income is about $3K per annum and median apartment price is would be about $200K.
But Guangzhou has a much higher property price to income ratio than either London or SF. So, the policy you suggest doesn't fix the problem you raise.
https://www.numbeo.com/property-investment/in/Guangzhou
https://www.numbeo.com/property-investment/in/San-Francisco
https://www.numbeo.com/property-investment/in/London