The latest GASIL has some info on this.
When asked "Should we pay for continued airworthiness management?", the CAA says "it is usually done better when done professionally. So even the CAA says that there will still be businesses out there who will not do it properly and who is responsible when they don't do it right............the owner.
I must check on this point from Malcolm that the CAA will set it's prices at such alevel as to force certain optional requirements on private owners. I am sure that EASA would have something to say about the UK using such a method to limit certain parts of the Law.
Regards,
DFC