Question

property taxes are based on

how much a property is worth.
when a property was purchased.
who lives on a property.
where a property is located.

Explanation:

Property taxes are typically based on the assessed value of the property, which relates to "how much a property is worth". Factors like who lives there, when it was purchased, or just location (without value consideration) are not standard bases for property tax calculation. Location can impact value (and thus tax indirectly), but the primary direct basis is property value.

Answer:

how much a property is worth