Believing you must invest right after college
While some people think spending all your money is the way to be, others believe you have to immediately throw it into the stock market or a house to start making McDuck-sized pools of cash. More important than that, Roberge says, is "getting your month-to-month cash flow solidified before you think about where to invest." Once you have a good idea of what you're able to safely invest, you've got plenty of time to consider your options and figure out the right investment.
Not taking advantage of a benefits program
Since people in their 20s often are enrolled in a high-deductible health insurance plan (that health plan's motto is basically "I'm gonna live forever!"), it's a good idea to take advantage of a Health Savings Account, or HSA. It enables you to pay for medical expenses with pre-tax money, and you don't even have to use the money in one year, like you do with a Flexible Spending Account. As you get older, your medical needs typically increase, so there's a 99% chance you'll eventually use this money.
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