Matte paint isn't anything to be too scared of. You can treat it basically the same as gloss paint, just be careful of scratches. It may not scratch any easier necessarily, but you will not be able to fix scratches through machine polishing. The protection that you use will make the biggest difference in keeping it looking nice and making it easy to clean. You will not be able to use a normal wax, but a ceramic coating or Jescar Power Lock Plus will work great. Be sure to checkout Matt's Wash and Talk videos for how to wash properly and maintain the vehicle.
For the initial prep, you can still go through all the decontamination steps that Matt uses, just be careful and test a small section with stuff like iron removers. Use care while claying as well.
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