Just to update people... Sildrae and I just got back from the front office. We've sorted out the problem.
Because my van hadn't been moved in a while, the manager had to tag it as a vehicle violation, as per corporate rules. He seemed rather spiteful about having to do it, too. Like he really didn't like that rule.
The reason it was marked "no tags" is because he didn't check the back--again, unlike Texas, Arkansas doesn't require front plates--and was trying to spend as little time outside as possible. A good thing, as the UV index has been outright dangerous lately. It was also assumed inoperable due to it not moving for an extended period, so it was a good thing that I drove it to the front to talk about it.
I gave him my plate number, and he made a note that my van has an Arkansas plate, and that there's no front plate required. He also noted down that it's operable, so everything is good for now.
However, this has me somewhat pissed at Sun Homes corporate. It shows that they're completely disconnected from the effects of their rules, and likely don't even care about those effects. Even the manager here seemed perturbed that he's forced to put potentially hard-to-remove stickers on the windows of the vehicles. That shows something.
I won't miss living here, especially with the new rules that keep getting instated. However, it's good to know someone is trying to make things right.