I've got them to come down to £80 - I've withdrawn from three chemistry ones (there's little point in my re-sitting them if they've no relevance to me getting into university whatsoever - this will also give more time to revise/work for my other exams).
Still not sure I should actually be re-sitting C2, but anyway, my teachers think it's a good idea and I guess one extra re-sit isn't going to kill me.