How the scam works:
At the dealership the agent who helps you with the paperwork for your new car is nice, but besides encouraging the unnecessary add-ons, also adds a ridiculous "Dealership Preparation Fee" to the invoice, ranging usually from $300 to $1,000.
When you query this, the dealer tells you they have etched the Vehicle Information Number on the glass (or peeled off the plastic protection of the car, or something similar) for you. This is an effective way to prevent theft and is done by applying chemical etching of the vehicle's serial number to your car window, which makes the car parts basically worthless. However, etching is something that would cost you $20 if you did it yourself.
How to avoid:
Tell them in advance you do not want this done. When you sign the contract for the car, look at the small print very carefully so you don't pay for something you didn't order.
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