My 126 was filled with water when I bought it. Many of the seals had failed and rainwater had started to pour into the interior over many years. The original owner of my car had passed away and the car had been an asset of his estate stuck in probate court. I almost considered not buying the car for this reason (the condensation on the inside of the windows was quite disconcerting). Once the water was cleaned up and the car was fully dried inside it was absolutely fine. No visiable water damage inside the car at all and its been one of the most reliable and cheap to maintain cars I have ever owned. For all intents and purposes it was a flood car.

People tend to get hysterical when it comes to water damage. They go on and on about toxic mold and the horrible expensive damage that happens to the car. Once you completely dry out the car its not really a big deal. Mold needs moisture to survive. If your car was covered in mold a nice trip to Arizona or Texas would dry the car out in a couple of days and kill all of it.

I also collect antiques and water damage is a fact of life when it comes to a 200+ year old piece of furniture. Even pieces of furniture that are in museums have been wet in some parts of their lives. Air conditioning is a recent invention and it was quite common for moisture to condense inside cool dark places where people like to congregate. Leaky roofs and flood waters also contributed to this. Its good people were not so hysterical over water damage back then otherwise some beautiful treasures would have been tossed in the trash in an effort to score some cash and new furniture from the insurance company.

Sludge and mud are a different story all together. Its nearly impossible to remove that from a car due to all the hidden spaces inside.