Mark Cuban: Why you should buy a two-year supply of toothpaste

Mark Cuban
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When it comes to , small changes are a good start.

"If you try to downsize your house, get rid of all yours cars and make all of these drastic changes, it's so overwhelming and you're not going to do any of it," says self-made millionaire Chris Reining, who banked over half his income to retire at age 37.

"The will lead you to be able to make the big changes."

You could start by saving on toothpaste, for instance.

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In a recent interview with Vanity Fair, billionaire Mark Cuban shared exactly how to do that: Buy in bulk and on sale.

"It's so hard to make a return on regular investments that … you're better off buying two years' worth of toothpaste when it's on 50 percent discount," he says. "There's an immediate return on your money."

Don't stop with toothpaste, either. This strategy applies to "any resusables or consumables that you have to have," the billionaire tells Vanity Fair. "When they're on a huge sale on Amazon, buy them, because chances are, their prices are going to go up. That's a real savings that you get to put in your pocket."

As for where to stash your cash once you start saving big: Invest it in "the cheapest SPX mutual fund you can find," says Cuban.

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