Liz Weston, NerdWallet Published 6:00 a.m. ET March 24, 2019

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A new ValuePenguin.com study reveals that the average respondent overspends eight times per month! That adds up to $315.16 of unnecessary spending! Buzz60

Certified financial planner Jill Schlesinger has seen smart people make some pretty spectacular money mistakes.

One client who repeatedly refused to buy disability insurance later developed multiple sclerosis. A doctor she knew put off writing a will and left behind a six-figure tax bill. A technology company engineer balked at her suggestion to sell some of his stock options, only to watch their value and his retirement plans evaporate when the market plunged.

Schlesinger, a CBS News business