Michigan teen flipped a Rolex at 16; watch business later topped $10m in sales

 At 16, Michigan student Mason Maressa spent his $3,500 savings on a vintage Rolex Air-King and sold it days later for about $4,000. He reinvested the money into more watches and gradually built Clocked In. Five years later, the 21-year-old says his appointment-only luxury watch business in Grand Haven has crossed $10 million in cumulative sales. At 16, Michigan student Mason Maressa spent his $3,500 savings on a vintage Rolex Air-King and sold it days later for about $4,000. He reinvested the money into more watches and gradually built Clocked In. Five years later, the 21-year-old says his appointment-only luxury watch business in Grand Haven has crossed $10 million in cumulative sales.