You determine the rate to charge your renter and keep 100% of the fee. In order to prevent theft and fraud (for example, a user listing an item for $10 and charging a $200 cleaning fee to circumvent RMW fee). There is a limit to $8 OR 20% of the rental fee maximum (whichever is greater). So for example, if you list an item for $100, you can charge up to $20 in cleaning fees (however most users charge no more than $10).