More than 43 percent of renters say they’ve found online rental listings that seemed fraudulent, and more than 5 million say they’ve actually been scammed—sometimes to the tune of thousands of dollars—according to a new report released by rental website ApartmentList.com.

The survey revealed that the most common scam is a “bait-and-switch” one, where a different property is advertised than the one that is actually available. The scammer is often able to collect a deposit or get a lease signed for the fake property. Another common scam is the “hijacked ad,” where a scammer takes a home that is legitimately for sale and poses as a fake landlord to collect funds. Apartment List also warns of a growing scam in which a listing property that is already leased is posted online. The scammer then attempts to collect application fees or security deposits from an unsuspecting consumer.