You drove home a clean, unmarked car. The next 12 months decide whether it still looks that way at trade-in time, and the dealership knows it — that is why they pitched you a $1,200–$1,800 paint-protection package on the way out the door. Permaplate, Diamondkote, Simoniz Glasscoat, Resistall, whatever the local brand happens to be. You can do the same job yourself for a fraction of that, and do it better.
Here's the dirty secret of the dealership add-on: it's almost always a one-time sealant wipe-down that wears off in roughly six months. After that, you're back to bare clearcoat and there's no one applying the next coat. Their package also stops at the paint — nothing for your wheels, your glass, or your floors. This kit covers all of it, and because you re-apply yourself, your protection actually keeps existing instead of expiring with the sales contract.
The row order is by importance, not workflow — start with paint and wheels (where the first-year damage happens), then glass, then floors. Skip rows that don't apply to your car (steel wheels, for example) and the kit still works. You keep the control, the cost, and the actual protection.