Is rust on the undercarriage a deal-breaker of a used car purchase?

YES IT EATS AWAY AT EVERYTHING.ONCE YOU HAVE IT ITS THERE FOREVER. RUNNNNNNNNNNNNNNN

Im in niagara falls new york and I deal with rust all the time, the converter rusting out on this suv is comm. and can be a big exsp. the most import. thing to look at is the fuel and brake lines they can be a very big prob down the line. Anything on a car or truck can be fixed or replaced but when it rust bad enough there is know fixing it. We have alot of good running cars sitting in junk yards here just because of rust. If it looks really bad keep looking for another suv and save yourself alot of money down the road.