Unfortunately the 50% "empty homes premium" excludes furnished properties, which means in practice almost all STR and 2nd-home properties escape it, so it doesn't really benefit councils like Cornwall that have a large proportion of such properties. The requirements are "unoccupied and unfurnished for 2 years or more" [1].
It seems more effective as an anti-blight law than anything else, encouraging people who have completely empty and unused property to sell it to someone who will do something with it. It's also supposed to target pure investment properties that people haven't even bothered to furnish, like those said to be owned by Russian oligarchs in London. Although I wonder if it will be effective there, since an investor can simply hire a company to throw some IKEA furniture in the apartment.
I'm not entirely sure if those were the goals, or if it started out life as a stronger proposal that ended up watered down. As is it's a bit confusing, since it seems to have a pretty narrow range of application that's easy to dodge.
Council tax increases also wouldn't have much of an effect on empty properties in central London because of the band system; tax on a property in Kensington would max out at £2124.04 before surcharges, or 0.02% on a £10M house. The property tax on a comparable house in Manhattan (based on checking MLS records for listings in Chelsea and picking a $13M townhouse) would be $44 000/year.
It seems more effective as an anti-blight law than anything else, encouraging people who have completely empty and unused property to sell it to someone who will do something with it. It's also supposed to target pure investment properties that people haven't even bothered to furnish, like those said to be owned by Russian oligarchs in London. Although I wonder if it will be effective there, since an investor can simply hire a company to throw some IKEA furniture in the apartment.
I'm not entirely sure if those were the goals, or if it started out life as a stronger proposal that ended up watered down. As is it's a bit confusing, since it seems to have a pretty narrow range of application that's easy to dodge.
[1] https://www.gov.uk/government/publications/council-tax-empty...