Howdy!
If you're not parking IN Ilium, you're parking on the road by the entrance. In the past, you get to drive in to drop off your stuff when you first show up, and you can drive in to load up when it's time to go. What I don't think you could do is drive in at any other time.
Parking on the road isn't that big of a hassle. I suppose there might be an advantage for some people to have their car right there, for storage or something, but me, not having a in-camp parking permit isn't a bummer at all. Once things get going you're all about the shuttle.
A couple road-parking tips: There are spots where the shoulder drops off steeply where you are not to park. If you park on the road during a time when there isn't someone there directing things, avoid parking near any tape and check your car when someone is there directing things to ensure there's not a note on your car asking you to move it. After that, don't think about your car for a couple days.
I recall seeing popup trailers (is that what you mean by PUP?), but you should get confirmation on that from someone other than me. You can see one in this
Ilium shot.I've got Ilium karma this year, happening along 10 minutes after every Ilium post.
Listening to:
Kruder and Dorfmeister