I'm moving from elsewhere in California — can I keep my old property tax base?

Often, yes. California's Prop 19 lets homeowners who are 55+, severely disabled, or wildfire/disaster victims transfer their current home's taxable value to a new home anywhere in the state — up to three times, in effect since April 1, 2021. That can mean paying San Diego market prices while keeping a much lower property tax bill than the calculator's default estimate assumes. Worth checking before you assume the full new-purchase tax hit.