I am a very happy new Cayenne Diesel owner after owning 5 Lexus vehicles. Unfortunately, I have an unknown spill, now silver dollar sized stain in the drivers seat - of course the tan colored seats! I have the perforated , leather seats. I have tried no fewer than a dozen leather cleaners, as well as several auto detailing services, to no avail. Does anyone have any experience or knowledge re repairing or possibly even replacing the lower portion of the seat ? Any idea if it would cost an arm and two legs? I'm in the Los Angeles area. Any info, suggestions would be greatly appreciated.