Scott DeNeve is used to being the youngest businessman in the neighborhood.
At 7, he tucked tomatoes from the family garden into paper bags and went door-to-door, selling them to neighbors.
At 9, he was mowing lawns -- with a vengeance -- eventually earning enough from 16 regular customers to pay for his own riding mower, plus two go-karts and bicycles.
At 24, he started his own real estate brokerage. That was five years ago. This month, Platinum Realty ranked 129th on Inc. magazine's list of the country's fastest-growing companies.