At twenty-one, Donato Callahan was buying real estate, working for the Department of Defense, and frustrated by how broken deal analysis was. So he built BrightInvestor. By twenty-five, he had several hundred doors and a growing SaaS platform.

Three ideas from our conversation stand out. First, his $500 test — he only builds AI features customers will actually pay for, not ones that sound cool. Second, his concept of the "vertically integrated worker" — stacking complementary skills within one ecosystem instead of chasing disconnected side hustles. Third, his take on AI's real limit: it gets you to third base, but domain expertise is what scores the run. Beginners who skip the learning curve get stuck. Experts use the same tools and widen the gap.

His default setting? Don't ask why — ask why not.

Listen to the full episode of Startup Stories from the Treehouse to hear the rest.

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