When shopping you may get fooled into thinking you are getting a bigger discount ........or getting more than you are for your trade in.
One thing to look for is the dreaded "extra window sticker".
You see, if a dealer puts $50 worth of extra "stuff" on a car that he charges $699 for he can show you another $649 for your trade-in or $649 discount from the inflated price he has on his window.
Below is a good example. The dealer (name hidden) tacked on a $699 "Paint Protection" package on his car so he can show a bigger discount when he negotiates it way with you. (Note that he even miss-spelled "shield" as he has "Glass Shiled" listed). His car will appear more expensive than our car with this official looking window sticker and he will then show you a bigger discount........ but it is not.
Personally speaking, I do not see the necessity of a "paint sealant" but that is just my personal opinion. It’s not 1964, your paint is not oxidizing, most every modern paint stays true and virtually all have clear-coat finishes.
Just my thoughts.