I wonder if those who feel they are appropriately qualified to carry out this maintenance realise the liability they will be taking on. That is not to say that they are not capable as they are exposed to it every day through their own profession. But this involves a totally different field. I'm sure the operators will take out separate liability insurance! And they reckon that medical liability insurance is expensive! (You can only kill one at a time as a doctor.)
Then there is the small issue of hull insurance...
Given that commercial imperatives are driving the issue, it seems that not a lot of oncosts have come into the equation