Welcome to the truck camper forum.
We see a posting like this every month and the same best advice, find the camper you want to use/purchase first.
If you are dead set on a 1500/F150, stop here and close this posting. You are not going to meet the goals of long term, more than a weekend, with limited carrying capacity of your truck. Sure, you can do it. But can you do it safely for yourself and others you encounter on the road.
As for extended time off the grid and away from it all, you need to plan backwards. Determine what you want and what to have on your truck and camper, then start going backwards on what is available in a camper and truck.
As an example, a thing I call the TP Factor. When conservative with water use, a person is going to use 17-22 gallons of water a week. So if you times that by 6 people, you have; 132 gallons of needed potable water. At 8.3 lbs per gallons, the weight becomes an important factor as well as where are you going to put that many gallons in a truck camper with only a 35-45 gallon tank. Oh, yeah. The water would weigh; 1,095 lbs, exceeding just the payload capacity of a F150, plus passengers, groceries and gear. Then you add the weight of a Camper; 2,000 to 4,500lb. You will now need to rethink your idea of not considering a 1 ton. Oh, yeah, don't forget 4X4 equipment weight on a vehicle, which is what most desire when considering going off for extended periods of time and boondocking.
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