11 Money Mistakes to Avoid in Your 20s (Before They Cost You Thousands) Your 20s are supposed to be about figuring things out — your career, your relationships, where you actually want to live. But there’s one area where “figuring it out as you go” gets expensive fast: money. The financial habits you build (or break) between 22 and 29 don’t just affect your bank account today. They compound — literally — into your 30s, 40s, and beyond. A bad decision at 24 can cost you tens of thousands of dollars by the time you’re 40, simply because you lost time you can never get back. The good news? You…