ALL REPAIRS ARE NOT CREATED EQUAL.
At some point in the past this Lexus was involved in an accident that required the left quarter panel getting replaced. This repair was done before the current owner purchased the car and they have no record of the collision repair facility that completed the repairs.
Later he noticed some rust appearing on the Left rear quarter. He brought it to CarSmart Collision Repair so we could take a look at it and see what it would cost to repair. We informed him that someone had replaced the quarter panel in the past and did not properly rust proof the repairs.