Best-selling author, TV host and personal finance guru Suze Orman has been inspiring Americans for decades to make better money moves and avoid serious financial mistakes.
She'll be the first to tell you that what you don't do with your money may be even more important as what you do with it.
Here are 10 major money don’ts — straight from the expert.
1. Don't be too quick to buy a home
Homeownership is part of the American dream — but buying one before you're able can lead to financial disaster.
"Sometimes it makes sense to own a home," Orman tells CNBC.com. "And sometimes, depending on where you live, it makes sense to simply rent."
That's particularly true if you're in an expensive city. Instead of pouring a lot of money into property, Orman says why not invest in the stock market? That way, you can grow your savings — maybe into a down payment on that home of your dreams.
A good way to get into investing is through an automated investment service like Wealthsimple, which will automatically adjust your portfolio to protect you from market turbulence.
2. Don't lease a car
In Suze Orman's words, you should "you should never, ever ever ever, lease a car."
If you lease, you'll sink your money into several years' worth of car payments and be empty-handed when the lease term is done.
Financing is a better option, but Orman says if it will take longer than three years to pay off the car, then it’s out of your price range. (You certainly don't want to consider one of today's seven-year car loans.)
Buying a used car is another way to go. Models that are just a few years old will have great safety specifications and the same audio-visual tech as a new car, at a fraction of the price.
3. Never co-sign a loan
When a friend or family member in need asks you to co-sign a loan, Orman says the only correct response is to turn them down.
As she puts it: "Don’t be afraid to say 'no to others and say 'yes' to yourself."
When you co-sign a loan, you become legally responsible for paying back the money. Life is unpredictable, and if anything happens to prevent the borrower from repaying the loan, you’ll be on the hook to make the payments.
Plus, if the borrower is so much as late on a few payments, your credit score can take a hit.
4. Don't take Social Security too soon
Our favorite financial guru advises Americans to avoid early retirement for a very good reason: It's worth it to delay taking Social Security until age 70.
"Every year you wait between your normal retirement age and 70, Social Security will add a guaranteed 8% to your eventual monthly payout," she writes, in AARP The Magazine.
She says delaying Social Security until you reach 70 will give you a monthly benefit more than 75% percent higher than what you'll get if you start at 62.
"Living well into your 80s and beyond is no longer some rare event," Orman says — and you want to make sure your resources will last as long as you do.
5. Don't sell stocks when markets are bad
When stocks are hurtling lower, investors tend to drop investments fast. This is a bad idea, says Orman.
Instead of dumping stock, she advises that you just keep investing the same amount of money each month, regardless of what the market is doing. Using this strategy, a bad month for the market becomes a good month to invest.
"I wish for 2008 again," she tells Yahoo Finance, referring to the year of the big market meltdown. "That’s when the fortune was made. That’s when you could buy stocks for pennies on the dollar."
If you train yourself to hold on tight through market dips, you’ll continue to build a solid portfolio with long-term earning potential.
6. Don't put blind faith in a financial adviser
It's important to have a financial adviser you can trust.
"Don’t think that they’re always going to have your best interest at heart, because probably they have their own best interest at heart,” Orman says.
When selecting a financial professional, make sure he or she is a "fiduciary," which means your adviser has a legal duty to act in your best interest.
During your vetting process, ask prospective advisers about how they'll be compensated for working with you, and about other services they can offer. This will give you a good idea of their motivations when they invest your money.
7. Don't borrow from your 401(k)
Suze Orman calls borrowing money from your 401(k) "the biggest mistake you will ever make" with your retirement money, especially if you use the money to pay off other debt.
A 401(k) loan is better than withdrawing money from your account, which will bring you a tax bill and a 10% penalty if you're younger than age 59 1/2. Plus, the loans typically come with a lower interest rate than a traditional loan.
But you might be barred from putting more money into your 401(k) for six months, meaning you'll miss opportunities to make pre-tax contributions that lower your taxable income.
Even worse, by taking part of your retirement savings out of commission even temporarily, you'll lose out on significant earnings if markets rise.
8. Don't let debt linger
"Debt is bondage,” Orman tells CNBC. "You will never, ever, ever have financial freedom if you have debt."
Still, she points out that not all debt is the same.
Mortgages and student loans can be considered "good debt," because home loans usually have fairly low interest rates and your degree is an investment that should generate a higher income over time.
However, credit cards have much higher interest rates. The longer you put off paying down your credit balances, the more money you lose. You can easily wind up paying for your purchases three or four times over.
9. Don't spend to impress others
It's human nature to want to impress others. But Orman knows from experience how foolish that is.
She once leased a fancy BMW and bought a Cartier watch with money borrowed from her 401(k) — just to impress a woman she was dating. She says it was "the most stupid thing I’ve ever done with money."
In the end, spending money you don’t have to impress others will leave you with shallow relationships and stressful bills.
Work hard, invest wisely, and reap your fortune when you’ve made it. There’s nothing more impressive than true financial success.
10. Don't spend on things you don't really need
There’s no better way to kick-start your savings than by playing the need vs. want game.
The next time you're ready to buy something, ask yourself whether you really need it. Is it a necessity, such as medication, food from the grocery store or a solid pair of shoes for work?
Or simply something you want — like another drink at the bar, fast food for dinner again or a second pair of knee-high boots?
"If it’s a want, just walk away. If it’s a need, then buy it," Orman writes. "Try this for six months and you’ll be shocked at how easy it is and how much money you’ll save."
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