Before placing an offer on any used car, it's important to verify that the seller has the necessary paperwork and to request the VIN. Potential buyers might want to request a vehicle history report using the VIN; these reports list information about the car's history.
It's important to ensure that any recalls placed on the vehicle have been met. According to RepairPal, six recalls were issued for Mercedes-Benz S550 vehicles between 2007 and 2014, and sellers need to make sure these issues have been resolved. It's also worth checking the car's service history to make sure the owner had the car serviced at regular intervals. Even small problems, like skipped oil changes, might indicate that the car has not been cared for properly.
Test drives are important to ensure the vehicle is functioning well, but it's easy to forget what to look for while on the road. Bankrate.com and other websites host checklists to use during all phases of the test drive, and potential buyers should follow through and ask about any problem they encounter during the test drive. Before offering to buy any expensive car, it's wise to take it to a trusted mechanic to give the car a thorough inspection, as a mechanic might be able to find problems that don't show up on a test drive.