Counties with populations over four hundred thousand and cities with populations over one hundred thousand may use tax revenue for:

(1) Acquiring, rehabilitating, or constructing affordable housing, which may include new units within an existing structure or facilities providing supportive housing services under RCW 71.24.385 (behavioral health organizations); or

(2) Operations and maintenance costs of new units of affordable or supportive housing.

Counties with populations under four hundred thousand and cities with populations under one hundred thousand population may use tax revenue for the activities outlined above, as well as to provide rental assistance to tenants that are at or below sixty percent of the median income of the county or city that is imposing the tax.