I would help you if I lived nearby! In terms of advice, I would think hard about the climates you will be traveling in. My build was pretty minimal... I used a lot of poly-iso insulation, along with a propane heater (for CO winters), and a roof vent/fan for hot days. Cooking was just on a two-burner propane stove, a 400W solar array and 200 AH sealed battery kept a fridge and electronics running. I didn't have running water, just several 5-gallon tanks. I moved between CO ski towns in the winter, AZ desert to warm up, and Pacific NW for the summer... so I tried to plan for those climates.
I'd recommend painting your van a light color if it isn't already. Get chains if you think you might run into mud/snow, and a tow cable. A cell phone amp/antenna can be helpful.
Hope that helps!
Learning by doing: silvopasture, raised beds, cover crops.
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