As she struggled to get on top of her spending habits, Nancy Trejos, a personal-finance reporter at the Washington Post, decided to hire a financial planner.

“I wanted someone who would really push me,” Trejos says.

Whether or not you need a financial professional—an investment adviser, tax accountant, estate attorney, or other type of expert—can depend as much on your personality as on how much money you have. Trejos, author of Hot (Broke) Messes—about hitting her financial bottom—says that just as she’s quick to go to a doctor when she’s sick, she wanted to turn to an expert to help with her financial health.

“If it’s not your full-time job, it’s easy to make a mistake or overlook something,” says Nathan Gendelman, director of investments at the Family Firm, a fee-only financial-planning firm in Bethesda.

Other people prefer to manage their own money and avoid the fees of professionals.

“My default position is to urge people not to use investment advisers,” says Yuval D. Bar-Or, author of Play to Prosper and an adjunct professor at Johns Hopkins University’s Carey Business School.

Bar-Or points to studies that show how over time the compounding effect of fees can eat into wealth. Investment advisers typically charge about 1 percent of assets under management per year. The nonprofit research organization RAND has calculated that one percentage point in fees translates into an investor’s paying more than $3,000 after ten years on a $20,000 account.

Bar-Or says many investors would be better off sticking with a diversified portfolio focused on index funds and other low-fee alternatives.

One 2007 Harvard Business School study also found that working with a broker didn’t necessarily improve investor returns and, in fact, people often selected better-performing funds on their own. Financial advisers, though, help with far more than just picking stocks, including estate and tax planning.

Says financial adviser Steve Lockshin of Convergent Wealth Advisers in Rockville: “Good estate planning can outperform good investment advisement every time.”

The Bernie Madoff scandal and the recession made investors wary of trusting just anyone. Complicating matters is that the category of financial advisers is often confusing. It includes planners who focus on budgeting, investment experts, and lawyers with expertise in estate planning and taxes. Anyone can call herself a “financial adviser,” so ask potential advisers about their education, experience, and qualifications.

Experts suggest asking friends and acquaintances to recommend good advisers. You’ll also find a list of the area’s top financial experts starting on page 91. Most advisers offer a free initial meeting so both the professional and the potential client can decide if it’s a good fit.

Here are nine questions to ask before signing up to work with a financial adviser.