Flood damaged cars don't just smell bad, they can be moldy, and many of the systems can simply never be trsuted again. Once a car has been flooded you never know when that electrical system is going to just decide that it has been through enough crap and just give up. Bacially, unless you're a mechanic and it's a really, really low price, don't buy a flooded car.
That's why it's important to know that there are now 200,000 flooded cars on the road. Most of these are in Texas, New Jersey, Pennsylvania, Kentucky, Louisiana, Illinois, New York, Florida, Mississippi and Virginia, but people who are having a hard time selling them in hurricane-ravaged states are starting to try to sell them in other states. Be warned.