I did a bit of research when I got my van last May. The true cheapest option is to do it yourself with Raptor liner or a similar brand. I think I did my van for under $1500 but had to rent a spray booth due to my living situation. If you have a good space for it at home, you can do it for under $1000. It is a lot of work though, do not underestimate how much work is involved with sanding the existing clear coat off. As mentioned before though, Chevyís factory paint jobs suck! I am also very happy with how it came out and the robustness of the paint thus far on a few off-road adventures with branches and things hitting the sides with no visible makes, which would not likely be the case with paint or a wrap.
I documented a lot of it on my van build thread if you are interested: https://www.sportsmobileforum.com/fo...awd-26987.html