My 2020 OG model Y had front PPF installed by a professional.  It looked great, but cost 5 times more than the same kit from TESBROS.   For my new Juniper Y, I decided to try the DIY route.  I spent a weekend on the project and the end results look great,   But...
 - I ended up doing the front bumper and one fender a 2nd time,  Otherwise, my personality would ignore the 90% success and dwell on the 10% imperfections.
 - Get the Ji guarantee.  It's a no brainer.  TESBROS customer service rocks.
 - Follow the prep instructions religiously.  No short cuts. You need a squeaky clean indoor work area.
 - Lots of light from multiple angles.  Some bubbles arer practically invisible until the light angle is just right.  Your body will also cast shadows on your work if you only have 1 light source.
 - Watch every installation video 2 or 3 times.  I used a tablet running Ji's videos for each panel while I worked.  So much useful information that is invaluable during the heat of the battle.