Kevin O'Leary: Don't make this home-buying mistake, even when mortgage rates are low

Kevin O'Leary: Here's when you should take on a mortgage

The average rate on a 30-year fixed mortgage was at 3.65% on Tuesday, according to Mortgage News Daily. That's the lowest since Nov. 2016. But don't let falling or rising interest rates influence your decision on whether or not to buy a home, says finance guru and star of ABC's "Shark Tank" Kevin O'Leary.

"What I hate about mortgages, they're very finite," O'Leary told CNBC Make It. "You owe money, lots and lots and lots of money. And you know, with certainty, regardless of what interest rates are, you're going to pay interest. That's what happens."

"Don't get lulled into an effective 'gee, the rates are low, that means I should go into debt,'" he advises. "It doesn't matter what interest rates are — debt is debt and you have to pay it back."

So the critical thing to remember about buying a home — regardless of rates — is that it should be a thoughtful and careful decision.

"Ask yourself this question before you even consider [buying a home]: 'Do I actually want to have a mortgage? Do I want to owe hundreds of thousands of dollars to somebody?'" O'Leary adivses.

"Maybe I should just rent for awhile, get a feel for the neighborhood I'm in and make sure that my job that's providing the income to pay for my life and my mortgage is stable."

If you decide it is time to take out a mortgage and buy a place, paying off your mortgage in a timely manner is then critical, especially for younger people, O'Leary says. That's because the longer you're paying off mortgage debt, the less money you can invest.

"Particularly if you're starting out and you've just had your first child with your significant other, you want to pay off that mortgage. You want to get rid of that so you can start saving money and investing in your future," O'Leary previously told CNBC Make It.

"Don't fall in love with being in debt through a mortgage," he cautions. "Fall in love with being debt free. Feels way better."

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Disclosure: CNBC owns the exclusive off-network cable rights to "Shark Tank."

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