OK, so as long as the lease co transfer liability it's most likely you will get out with only the admin fee. Wait till you get a PCN to Hirer in you own name and come back with the info on that. The parking co are required to send additional docs with the Hirer PCN, but they never do (or at least we have never seen them do so yet!), so the liability transfer fails - it might require going as far as small claims court before they back down of course.