It seems there are a small handfull of guys that want each trade to be a highly exclusive club.
You wouldn't want a plumber changing a light bulb or a painter changing the toilet paper. I guess they think that it is beyond the capacity of the human brain to learn more than a single trade.
The reality is, there are many people who work in an office who can do a great job doing multiple trades. I've a neighbor who is an engineer, doing explosives design and testing, that re-built his own house. He really did do it all, and did a fine job.
He wanted to modify existing trusses so he studied the engineering involved and properly did them. He did the plumbing, electric, framing, concrete, sheetrock, tile, trim, etc. and he did a fine job with all of them. When he got to something he wasn't sure of, he would consult with a trade professional (he has plenty of friends in the trades). He properly permitted the project and had all his inspections done.
His trim work is exquisite. As a hobby he builds furniture.
