Hurricane Harvey damaged about a million cars and trucks. Many will be transported to other states to be sold. The danger is in buying one without knowing it was damaged by flooding. For cars covered by insurance, a Carfax report can show if the vehicle suffered flood damage. Carfax tracks the repair history of vehicles and currently offers free flood reports. Some owners try to clean, repair and sell flood-damaged cars. So experts suggest sniffing around the car or truck to see if you can smell mildew – a sign the car has been wet. Check under the carpet and in the trunk for mud and rust. Replacement seats and carpeting should be considered a red flag. If in doubt, drop the purchase. A car rotting from the inside out could cost you thousands of dollars to fix.