I know a guy, he was a machinist at Homestake Gold Mine in Deadwood, South Dakota. He was a machinist at the mine and over the years built his own machine shop at home. At one point Homestake hands had a pretty good business manager. In lieu of wages, the business manager got a bonus tied to the price of gold in their contract. Gold went up. So this guy made pretty good money and he sunk a bunch of it into his machine shop where he worked on automotive and guns in his spare time.
I had a transmission he wanted, so I sold him the transmission for so much cash and setting up a differential for me. I didn't know much about my transmission except it came from a car that was in the garage that burned completely to the ground. It burned so hard that it started the next-door neighbor's house on fire. He knew about the fire and we made the trade. When he got it apart, he was so happy that besides setting up the differential, he said: "you have some credit coming".
I went to pick up my differential at his shop and that was the first time seeing it. I pull up and it's a log cabin, a giant log cabin built with logs 18 inches in diameter. I go in the shop and it's full of CNC machines, lathes, presses, and everything a guy could dream of from big to small. Homestake shut down and he went home to work his own shop. I imagine he bought more equipment at the Homestake auction sales too.