The man the the metal machine tools was actually one of fathers good friends. My dad, like his friend worked at the coal coal mine. My dad’s “hoody” was running an auto body shop business on the side. He broke more than a little even with his union job at the mine and made his gravy in the 70s and 80s buying somewhat beat up cars with solid engines and transmissions, putting a bit of lipstick on the pig, and then selling them for double or triple the investment. At any one time he usually had 4 to 5 running vehicles parked in our driveways on top of the family’s personal vehicles.
I would say that he pulled in about $10 - 14K a year in the early 80s and I know he did not report that income. That is roughly $35 - 45K in today’s money.
I myself bought a 74 Camero for $500, drove the hell out of it for 2 years painted it up and replaced the interior from out of a totaled vehicle,
I have two brothers who buy cars for dirt and turn them around for money. I can relate to your father’s friend.