Watch out for exorbitant ­municipal bond fees. Recent spikes in yields on high-quality municipal bonds have made them attractive again for investors seeking tax-exempt income. But many bond brokers charge investors more than 3% on the total purchase price—or about $450 for $15,000 worth of individual muni bonds, which are exempt from federal taxes and possibly state and local taxes. That high a fee can eat up an entire year’s worth of bond income. And the fees easily are hidden because instead of charging you a set commission, brokers mark up the price of the bonds they’re selling by an undisclosed amount. Also, muni investors tend to focus on bond yields, not the overall price they pay.

Self-defense: Ask your broker for the CUSIP, a unique nine-number/letter identifier, of the bond you want to buy. Type the CUSIP into the search box at EMMA.msrb.org—which is the Electronic Municipal Market Access (EMMA) site run by the Municipal ­Securities Rulemaking Board—to check what other customers paid for the same bonds. Use that information to negotiate a better price.