I think as well as UBI we should have universal basic land. Grant everyone the right to a share of an apartment building that doesn't exist yet on a specific plot of land on the city outskirts. Few people will want to actually group together and build apartment buildings on vacant land on the city outskirts, but I would hope that just having the option would bring down the price of land for everyone. Private options would have to actually compete with the basic public option instead of taking advantage of their customers having no alternatives. Same thing that already happened in telecoms.