Scott, you don't even have to camp at an event like DoK. It's not an immersion event, it's a timeline event. The difference being that at an immersion event the idea is to literally 'live' history, and be fully immersed in a given time period with all the camping, food, clothing, etc. Often these are just for the participants and may be private events.
A timeline event on the other hand is specifically geared toward public education. So there's no requirement to go all in on the encampment side of things. DoK has a modern camping area for those who want to camp but lack period stuff. And if you don't want to camp all, there are plenty of people who stay at local accommodations. All you need to participate is yourself and something to wear.
If your intent is to use a period tent and camp out, the best thing to start with is literally the tent itself. You can fill it with all the modern accommodations you want to haul out there as long as you keep your tent closed. I keep my tent closed because I don't have all period storage containers etc. The period furniture I do have stays on the outside of the tent if I want people to see it, and all my plastic totes and junk like that just stays on the inside. I'd like to eventually move to a full period encampment but that takes time and money like everything else in this hobby.
So really, to just camp out and get started, all you need is the tent. Then start building from there.
Now once you start building up that camp to sleep in period style, you'll probably want lots of storage chests and woven baskets to keep things in. You'll want a rope bed or some variant. My rope bed is conveniently the perfect size to fit a twin air mattress. And finally a set of trestle table legs to put boards on, and now you've got all the basics. Storage, place to sleep, table to put stuff on. The chests all double as seats too. Then you can start getting more of the convenience items from there.
