Thanks for all the input.
I do get by, but with the renewals of both instructor and examiner ratings this year, I need enough coming in to justify the expense and effort.
I've been charging in line with the rest of this thread, typically £150 for a full skills test, and between £60-£100 for an LPC depending on the candidates affiliation with the club I'm at. I had heard £200 was more the norm, but I guess I'll just keep doing what I'm doing.