" 'an honest days work for an honest days pay'"
And that's what it's all about. I'd hate to think what a full playfield restore would cost.... no doubt well less than $50/hour.
EDIT: Meaning... it would cost well less than it's actually worth.
Case in point - The Genie playfield. I lost count of the hours. You could probably buy half a dozen playfields with the amount of time I spent on it. But I learnt a lot, and I kept pushing myself to learn more. I've seen El-Timbo's work and his playfields are unbelievable. We are looking at doing FOUR Embryon's in one hit. The hours will be very intensive, but a flat fee is quoted. The whole idea is to preserve pinball - not to make it unaffordable. These days, astute collectors are informed of the time and effort and in most cases, more than happy to do the work.
It really helps if you love what you do. There's no issues with working longer hours. It is part of the process.