Depends on your definition of “success.” Countries such as Holland, France, Canada, Germany, and China all have caps on the amount by which a landlord can increase rent in any given year, usually by law it’s less than 5%, or indexed to inflation (but with 5% as the max). These laws are incredibly popular with renters and have been around for decades.
Berlin implemented a hard rent freeze in 2020 which was extremely popular with renters, but not with landlords, naturally.
Can you name some countries/policies where it’s a continuing success?
Depends on your definition of “success.” Countries such as Holland, France, Canada, Germany, and China all have caps on the amount by which a landlord can increase rent in any given year, usually by law it’s less than 5%, or indexed to inflation (but with 5% as the max). These laws are incredibly popular with renters and have been around for decades.
Berlin implemented a hard rent freeze in 2020 which was extremely popular with renters, but not with landlords, naturally.
However, rent control isn’t just a hard price cap like back during the war, there are many nuanced aspects, see here for information: https://www.theguardian.com/commentisfree/2021/apr/23/berlin-rent-cap-defeated-landlords-empty