Free: Contests & Raffles.
Bring extra spare tires and your best tire changing equipment. Some of the roads in there will sipe your tires for you, but good. Check in early because you might have to drive awhile to get to the areas that are open. Depending on what areas are open it might be easier to enter though one of the gates on the perimeter after checking in.
I was in there 2 weeks ago. The roads were no problem. Very cool area, almost too big. Only saw a few fresh tracks though.
The alkali has been hit hard the last couple years by the tribes, anyway back to my friends being there. At the gate they were asked to see their orange which they showed, this was just as an indian guy walked past them w/out his orange.