Check the city parks web site, the fee is to use the ramp lanes regardless of where you park. It is enforced by issuing tickets to vehicles with trailers without the permit in the city parking areas and on nearby streets. It is not enforced on a predictable basis but I have heard many complaints from people parked on the street who have been cited. Like tjcarroll I buy the $150 permit and easily used my 15 launches by mid August, at Magnuson and Shilshole (Eddie Vine).