Hey Theutzy,
First of all: Welcome to LCPDFR :) If there is anything you're not sure about or you want to know, please feel free to ask :)
Regarding your topic;
The skin of the vehicle is easy. I'll have it done within a day. It takes about a day because I'll have to make the logo myself, as there isn't any good / high resolution one available on the internet.
The car on the other side might be a bit of a problem. I've never seen a 2015 Caprice with a lightbar on it, and after some google work, I didn't become much wiser. I don't think it it possible to get this specific car, unless you contact a modeler.
I hope I've informed you enough, and if you'd like me to still make the skin for other vehicles, please send me a PM or respond to this comment.
-Daniel AKA BlackNoise