Marin approved a $600 fee for licensing a short-term rental under a new rate structure it will implement this fall, but it will only charge half that amount for people who host guests in their primary residence.

The Board of Supervisors approved the fees on Tuesday under the new S.T.R. rules they adopted in May, which capped the number of vacation rentals in unincorporated Marin for the first time. The two-tiered fee system is intended…