Cabinet shop, automotive, some kind of light manufacturing.
Bitcoin mining, 3d printing, all seem like bubbles. What are you 3d printing? If you have viable product, just injection mold it. Bitcoin, really? Airbnb? Nope. Good old fashioned stable businesses.
Build trailers. Build stuff, that you can put on skids, wrap and wholesale, then work on making more and more. Or fix cars for $150/hour. Or build high end cabinets with CNC equipment and human input that go into high end kitchens.
I work full time as an electrician. I make pretty good money, in fact my schedule is insane and i work a ton if overtime, way above the normal hours a 9-5 office worker would ever dream of. For that I make good money, but I don't love this.
My dream has always been opening my own company.
Have a registered business, built my website in my own time, learned Figma/Illustrator, created my own logo, letterheads, business cards, site. Spent money above and beyond to outfit my truck with ladder racks and sliding storage under a canopy. Carry insurance.
On my brief time off, do side jobs (insured, with permits). Analyze each how they went. Did I sell well? Did I charge enough? Did I finish in the amount of hours I thought I would? If not, keep iterating.
I also workout 6 days a week and read books for leisure and want to run a marathon. This is probably "hustle culture" and I feel like anyone who uses the words toxic hustle culture will never start a business on top of their 9-5 without significant outside help like inheritance, partner bankrolling them etc.
In short if you have a job and want to run a business, there is a period of time where you need to do and juggle both. If you think that's toxic hustle culture then.. don't?
This is kinda how I imagine Elon Musk's day most days. Go to some meetings. Say uh-huh, yep, sounds good a lot. Browse X on his phone and argue with blue-haired feminists. Lol at how he "owned" them (in his head).
Basically, be rich, be a boss, have a company that more or less runs itself with or without you, but be on top of it anyways. And spend your days doing whatever bullshit you want.
I take it you're not rich, so that's a strike against you. So you need to start some business, build it up to a substantial size, with skilled employees who can run it, yet keep yourself at the very top of the food chain. Pay yourself a large salary, do a bit of work here and there, and do whatever the F you want all day while other people make you rich(er).
Did you expect any other answer, honestly?
I know a few people who'd rent it to work on cars
There is such demand for small shop space for a few hundred a month. I wound up renting a fenced gravel yard/lot with a seacan (shipping container). The right garage in the right area, yeah I'd probably rent that. I see them go for $300/month which is reasonable (2 car).