Last weekend, an "innocent child", took a small piece of a metal can, and scratched par of my blue car trunk (color code 52D), leaving some deep white lines.
What product do you recommend me to apply? what do you recommend me to do?
The costs for paint this small part is about 80 bucks.!!

Leave the scratches they look cool.I have them all over my 02 wrx,and plan on leaving them because **** flies off the road all the time.

Technica- Good outlook . . .

To the application question: don't buy any scratch remover or any of that crap= waste of time

Buy some good mothers or meguiars canuba wax. That will do the trick for a little while then they come back again.

WRX Rush

what about the subaru touch-up paint? Does it work or does it work the same as nail polish on my rusty ten speed?

Nah, I used to work at a body shop. . . you see people coming in all the time where they used touch up paint to fill in scratches and chips that could have easily been buffed or fogged out. Since the paint doesn't have clearcoat and isn't baked like Subaru baked their parts from the factory in about a year they come back looking like someone used the wrong color. Then it costs just about 2.5 times what it would have costed to get it fogged or buffed out.

"Go big or go home"
WRX Rush