RE: what are the nesecities to set up a elk camp.
Since you're car camping you can be as extravegant as you wish - Just remember that you will have to pack everything back up again on the last day.
In addition to all the normal camping necessities (tent, sleeping bag, stove, lantern, etc.),your hunting gear, and your game care kit, you may want to bring a target so you can shoot a couple of arrows each day just to assure yourself that everything is okay.
Get a water filter to render river water safe.
Bring a big, airtightplastic bin to put your hunting clothes in as soon as you get back to camp, or at least before you light a fire or start cooking dinner. You don't want to stink them up with smoke and food smells.
You may also want to think about a boot dryer or a spare pair of boots.
If you're new to camping in general, I'd be happy to get more specific there.
-- FLIX