Total discloser does not necessarily apply to all sales, it is a "buyer beware" transaction.
Here are a few tips that should help.
*Ask to see the title of any used car. Check the date and place of transfer to see if the vehicle comes from a state that recently experienced flooding, such as New York or New Jersey. Keep in mind that the title will only indicate flood damage if the insurance company officially totaled the car. Also, consider CarFax.com.
*Check for signs of rust and mud in the trunk, glove box and beneath the seats and dashboard. Look for rusty brackets under the dash and carpet, discolored upholstery and carpet that fits poorly or doesn't match.
*Test everything: the lights, windshield wipers, turn signals, cigarette lighter and radio. Check the heater and air conditioner several times, and look in the vents for signs of water or mud. Make sure all gauges on the dashboard are accurate and in working condition.
*Think carefully before agreeing to purchase any car over the Internet sight unseen, especially if the vehicle comes from an area that has suffered a flood or other disaster
*My best advise is to have a certified auto mechanic's inspection.