I just purchased an '01 CL600 AMG. Long story short, the car needed a new battery and alternator when I bought it. The car sat at a garage for a week, before I told them that I would change the alternator, and not them.
I had the car towed home and a couple days later, I noticed the front left side bottomed out after a week. Buying the car, was a 3 week negotiation, so I know the sitting car was completely level before I brought it home.
I just installed the new battery, so the car is able to run a few minutes alone from battery power. The passenger side suspension went fully in the extended upward position and does not lower down. The drivers side, (both front and rear), will come up to normal level once starting the car, although, it is still lower than the opposing passenger side.

So, the car sat at a normal level when I bought it and during my pre-sale inspection when starting the engine, etc. I bring it home, the front driver's corner loses height, and the passenger side is in an above average height.
Any ideas? Could all this be the result of a non-functioning alternator, not supplying the necessary power to where it needs to go?

The driver's rear window was open about an inch for 3 days before I brought the car home, so it was exposed to days of rain. A large water puddle formed on the front drivers foot area and the rug in the rear driver's side passenger was heavily saturated. I'm unsure if anything electrically related is in this inside floor zone.