I fished and camped for years under a cap. Built a bed with storage from 2x8s and used a cap built with a door in back. Carried a Hibachi to cook steaks while fishing or hunting (never use for heat) Amazing how one body can warm a small cap. Carried a -30 degree sleeping bag and never got too cold. (had to tuck my nose in a few times)
A toilet seat can be had that snaps onto a 5 gallon bucket.... line with a heavy trash bag and snap on the top.
A good cooler is all you need for most items. Ice will last about two days.
