For some entrepreneurs, the best education comes from the real world—by making mistakes, learning from them and by seeking advice from business owners who've failed and succeeded before them.
A good candidate to learn from is Marcus Lemonis of CNBC's "The Profit." The CEO of Camping World and Good Sam, he has his hands in more than 100 businesses, and he's planning to add another one—Crumbs Bake Shop, a once-popular cupcake chain that went into bankruptcy in early July.
He dispenses advice every day on social media and via e-mail. Now on the "The Biz Fix," he's answering some of the most popular questions.
What's a good type of business to invest in and why?
Good investment opportunities include businesses with relatable products and services that go beyond fads to possibly last for generations.
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Lemonis also likes businesses that have diversified product offerings. At Crumbs, he wants to sell more than cupcakes. He and an investor group plan to turn the bake shops into snack food destinations. He'll sell products from his other brands, like Mr. Green Tea, Matt's Cookies and Sweet Pete's candies.
"You can't run a business on just cupcakes," he said. "When we reopen, we're going to have a diversified offering."
How important is listening to your gut in business?
Lemonis frequently makes handshake deals based on gut decisions. But he doesn't invest his own money purely on a whim.
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"Your gut is good to give you some sort of reaction, but it doesn't trump listening to the numbers," he said. "If the numbers say one thing, and your gut says another, always defer to the numbers."
Which of the 3 P's—people, process or product—do you consider most important?
Investors should make sure that the product they're betting on is a good one, and that the process behind it is solid. If they aren't, it's not a dealbreaker because those things can be fixed.
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"What you can't fix sometimes are the people," he said. "So the people side of the business is the most important part of any business, small medium or large."
Do you worry if an owner gives up control to you too easily?
Passion means a lot to Lemonis. He prefers that owners fight before giving up control to him because it proves they have a passion for their business.
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"No matter what anyone tells you, push through any times that might get tough and follow your dream," he said.
Follow Marcus Lemonis on Twitter @marcuslemonis.