I harp a lot about "overhead". I found that if I learned how to do things myself, I didn't have to pay others to do a lesser-quality of work.
So, over the years, I got damned good at automotive stuff. I'd buy a "boogered" car for under Bank Loan. I'd borrow Bank Loan against the title. The cash difference paid for necessary parts. Do whatever repairs were needed. Drive it and de-bug it, and after six months or so, sell it for wholesale.
I learned carpentry, plumbing and electrical wiring. And then how to do asbestos shingles. My engineering work taught me a bunch about structural stuff, as well as concrete.
None of this was overnight; no "instant gratification". Just plugging along through the years.
My opinion: Anybody can do it. All you need is the Want To.
In 1992/1993 I put it all together and built my own house. I hauled trailer loads of lumber, pipe, windows and wire and fixtures to the site. I did hire the "basic box" work, to my plans and specs. After the drying in, I had two guys help with the sheetrock ceiling, and one guy and I did all the panelling, insulating and wiring. I hung all the doors and did all the plumbing and cabinetry. My wife did all the staining. The total on-site time for me was some five months; about a month for my wife.
I gotta admit I did beat my left thumb plumb into submission.
14 acres, 1,400 sq ft, garage, water system, all furniture and furnishings, carpet, etc: $33/sq-ft. Plus my and BossLady's labor. And a bit of scar tissue...
IOW, never quit learning.
Art
I guess it all depends on what you want, and how bad you want it.