@impastu Ceramic should go on after PPF, otherwise PPF adhesion could be a problem. No more than three coats of Ceramic; clay bar first. I put 3 coats on my 2019 M3+ have only used beadmaker since. Do not put ceramic on every four months. Maybe, if you must, add a coat every 12-24 months. PPF needs to be waxed, ceramic coated, etc. to shine. It's duller than paint. Ceramic coating should be treated like any other sealant/wax. After two washes, I quickly reapply Beadmaker. Nothing special. Note: I didn't have PPF put on either my 3 or Plaid, but did invest in, and installed, mud flaps ASAP.