If you call Antonio Sustiel and he doesn't answer, his voicemail guarantees that he'll get back to you "within a few minutes."
It's this type of round-the-clock work ethic that has helped the grade-school dropout become a self-made millionaire. As the founder and CEO of Flooring King, Sustiel turns piles of wholesale laminate flooring into cash.
The Israeli immigrant has a true rags-to-riches story. He dropped out of school at age 10 to work for his father's construction company, and then served in the Israeli army starting at age 18.
When he landed on U.S. soil at age 23 in 1987, he had $400 in his pocket, Sustiel says on CNBC's "Blue Collar Millionaires." He moved to Florida determined to make his own American dream a reality.