You'll hear plenty about the dangers of lead-based paint if you try to buy or sell a home this spring. You can be forgiven, however, if the warnings leave you wondering what to do.

This much is clear: According to a federal law that went into effect in December, sellers of homes built before 1978 (the last year that lead-based paint was sold) must give buyers a brochure from the Environmental Protection Agency outlining lead hazards and ways to reduce the risk of lead poisoning.Sellers must also disclose any test information they already have and allow 10 days for a lead inspection, if the buyer wishes to pay for one. Expect to pay $120 to $250 for the necessary tests, depending on where you live.

Lead chips and dust are especially dangerous for children under age 6, whose nervous systems are most sensitive to the poison. So if you have kids and you're in the market for an older house, you will probably be better off having a thorough risk assessment done.

If you're planning to remodel by tearing down any walls that could raise dangerous lead dust, it's a good idea to go for the most expensive testing option, X-ray fluorescence (XRF), which peers through layers of paint to detect the presence of lead.

The price for XRF testing varies. In San Francisco, for example, whole-house testing costs $500 to $1,000, but can cost as much as $1,500 for a very large house. On the East Coast, the price range is roughly $350 to $500.