Teams take it to all different levels, but it's not hard to get started. In 2013, a couple of us "broke in" and "graffitied" the bot. (Came in one night and spray painted the frame). It was dead simple and very fast--dry by the time needed our the next day. The spray paint shows more than its share of battle scars, but it works particularly when you're just going for scout/in-match recognition. That plus some nice sponsor panels is really all it takes to started. Oh, and good bumpers (most years), that's a must. I did spindle panels in thin polycarbonate: cut with scissors, print sponsors in mirror image, stick on back, then spray paint the back. Velcro in place. We've been doing it the same way for years, though now the frame is an automotive paint sponsorship.
In-shop it's a couple hours max, plus money for a few cans of paint, some thin PC, and a pack of clear shipping labels. You won't be 254 or anything, but it's
enough to make it pop a little.