Dreaded Car Makeover

In some shows, for whatever reason, the kids or even just total strangers who are acquaintances of the main character's child, or even both, decided to modify the parent's (usually the dad's) car with various decorations, whether it be a new paint job, or adding new items to the sides of the car. Problem is, they usually do so without the parent's permission, and the result is usually ghastly to the owner.

Live Action TV

 * In Lizzie McGuire, Matt was discovered to have artistic talent. The McGuires decide to not interfere with his gifts. Of course, by the end of the episode, they end up having to interfere after Matt ended up painting his dad's car with a lot of paint and other decorations, causing the parents (or rather, the mom, as the dad was too shocked and mortified at Matt's paint job of the car to even say much outside "That's my car...") to lecture Matt about limits as to what art he needs to express. The one plus side is that the paint job also obscured the dent when the dad accidentially smashed against a mailbox, although the dad's reaction indicated that he didn't care, and was still very upset with Matt for what happened to his car.

Western Animation
"Lisa: This is the most thoughtful thing anyone has ever-- (Homer opens the door to the summer home for some reason, the viewers see only his shadow) Homer: Sweet merciful crap! My car!"
 * In The Simpsons episode "Summer of 4 ft. 2", some hipster friends whom Lisa made in order to fit in decorated a car with seashells, some spelling out "Lisa Rules" to show they haven't given up on her, even when they did discover her more geeky nature. That car was the family car. Then Homer steps out of the summer house and sees what happened to his car, and is genuinely shocked and horrified at what happened to it:


 * The car is then attacked by various seabirds as the family leaves Little Pwagmattasquarmsettport, with Marge also complaining, citing that the least the other kids could have done was wash the shells of before gluing them to the car.

Other

 * One promo for The Hub involves Dan from Dan Vs. coming outside to discover that his car has been "bedazzled" by Pinkie Pie from My Little Pony Friendship Is Magic. Watch it here.