The number of waterlogged wrecks on the market has more than doubled in the last five years, and the recent events in the Midwest are likely to result in even more salvaged cars being resold-often thousands of miles away from where they were damaged.

Despite the fact that most flood-damaged vehicles will be written off by insurance companies, some will make their way back on to the used-car market, rebuilt and disguised as ordinary used cars with clean titles.

And flood damage can be hard to spot; a car that’s been underwater will literally rot from the inside out.

Consumers shopping for a used car should be on high alert for signs of hidden damage and potential fraud. To help you avoid cars with water damage, Carfax offers these tips:

• Check:

Check the trunk, glove compartment, dashboard and below the seats for signs of water damage such as silt, mud or rust.

• Examine:

Examine upholstery and carpeting closely; if it doesn’t match the interior or fits loosely, it may have been replaced. Discolored, faded or stained materials could indicate water damage.

• Turn on:

Turn the ignition key and make sure that accessory and warning lights and gauges work properly. Make sure the air bag and ABS lights come on.

• Test:

Test lights (interior and exterior), windshield wipers, turn signals, cigarette lighter, radio, heater and air conditioner several times to make sure they work.

• Flex:

Flex some of the wires beneath the dashboard. Wet wires will become brittle upon drying and may crack.

• Smell:

Take a whiff for musty odors from mildew.

• Visit:

Go to a trusted mechanic for a prepurchase inspection. Always get vehicles checked before handing over any money.

• Ask:

Ask to see a detailed vehicle history report.

Carfax Vehicle History Reports can reveal many hidden problems from a vehicle’s past, including flood titles, and will indicate if a vehicle has been titled/registered in at-risk areas during flood and hurricane seasons.

If the seller does not offer a report, use the 17-digit Vehicle Identification Number (VIN) available on the dashboard to check the car’s history at www.carfax.com.