Oakland also has a vacancy tax (2018 Measure W, https://www.oaklandca.gov/topics/vacantpropertytax), but it is limited to $6k per year per property, whereas San Francsico’s 2022 Proposition M increases to $20k per unit, which the plaintiffs argue is so burdensome that is not simply a revenue-raising tax but it compels the owners into business against their will (https://www.courthousenews.com/wp-content/uploads/2023/02/sm...).