100% is the level whereby 100% of the profit a landlord makes will be due to the quality of the improvements and 0% will be due to land speculation.
A landlord owning a shitty building in a hot location will lose money. Hopefully a lot. That is by design. They sell up, somebody demolishes it and builds something better and denser and therefore makes a profit.
>Private money already wants to develop their unimproved land
All the private money in the world isnt enough to convince land owners in San Francisco to demolish their low density housing and build high density housing to accomodate all the people who want to live there.
Tax them on the land and not only will they stop NIMBYing private money at every opportunity theyll sell up gladly to property developers to avoid paying their eye watering LVT bill.