I would fix it as inexpensively as possible. Many scratches can either be touched up with a paint pen or brush dipped in good automotive paint with a perfect match. Usually a good buffing will eliminate most of the scratch depending how bad it really is. If you are trading the car in it more than likely will make very little difference because dealers tend to only give you trade in value anyway. There are many buyers that really wouldn't even care about a scratch. The more picky buyers will buy a mint condition 2019 Passat because for the most part a car that new should look almost brand new. I don't believe in fixing up a vehicle to trade it in. If Maaco fixes your scratch they won't say anything because the scratch shouldn't be visible.