Being an owner who hires crew I have researched this in detail.
My insurer is Pantaneous.
Most insurance companies in assessing claims will seek to impose liability wherever possible. If the issue, especially where there is another claimant as in public liability, was caused by act or omission by a paid skipper
or crew they will immediately seek to recover costs from the Skipper
or Crew. If the Skipper or Crew is unpaid and their details are attached to the policy there will be full coverage on the owners policy.
As a minimum a delivery skipper should be covered for public liability, or alternatively not have a cent to his name. The other alternative is for the owner to contract
this skipper for other purposes and attach his name to the policy as an approved skipper unpaid.
In regard to medical
coverage a paid skipper is generally not eligible for medical
claims from the owner under a boat insurance policy. Again if he is unpaid then he is eligible. The same comments made above apply.
Adequate insurance is expensive, for obvious reasons. You would normally only find it with companies that contract
out delivery services, but commensurately they are expensive.
Personally, I would not let a paid skipper on my boat unless he can demonstrate full insurance coverage, and I have done that in the past for short deliveries. For longer trips a contract for other services can be negotiated and services for skipper and crew delivered at no cost with skipper and crew CVs submitted and approved by the insurance company.
I hope this helps.