The real money I've made over the last 30+ years was in real estate. Single family rentals, small apt building.
I had a cousin who graduated in the 70's with a Masters in Psychology. Unable to find a decent job, he started buying run down homes, lived in them while he fixed them up and over the years built a small fortune.
Admittedly he was a bit unusual and died before he should have :-)
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I'd buy a duplex that needs some cosmetic stuff, live in half, rent the other out. When it's in good shape and you can afford another, repeat.