I fully endorse the views expressed by both you gents. The mechanics, denters, painters, lathemen, they are all around because of their skill in a greater or lesser degree. The person who commissions the restoration is, in my opinion ( and you may not agree...) is the "chef" who has to get the "recipe" right so that the end product is as per his wishes. It is vital that he is sure in his mind about the right mix of quality, effort, expense etc........and be prepared for unexpected eventualities incl being taken for a ride. It is upto him to gauge who can deliver how much and how well. He may not possess the skills reqd but must know how to extract them from those who do. He must expect no "mercy" or consideration and has to be a step ahead and be result oriented when making payments.
Over the years, if working with the same people ( and I totally recommend doing that if possible) a working relationship evolves and they know what you want / expect which is a big plus point.
This in short is the essence of my experience in 20 + years after putting together just as many cars ranging from a humble beetle to a ginormous vulgar Cadillac on one end of the spectrum and from a total ....and I mean total....rebuild ( a Datsun 240Z) to just a light refurbishment 
And as the saying goes: "experience is what you get when you don't get what you want"
This may sound odd but I feel the "X" factor in ANY resto' worth it's name is that "labour of love" element. The pleasure of getting the job done.
