Doug, you got me to searching that Commercial Truck Trader site, and I found this '90 Doka Unimog. Not sure if it qualifies as 'low cost,' though, at $75K...
Don't know how to add the link but there is a 01 Mitsu Fuso 4x4 box truck on the Spokane craigslist in St Maries ID. Sounds like it is optioned pretty nice for a expo offroad rig. You could make a camper out of it fairly quickly.
There sure are a lot of options out there.
Here's the listing: http://spokane.craigslist.org/cto/3063851809.html
2001 4x4 Mitsubishi FG Fuso 152.000 miles 3.9L 147HP 5 Speed gear box P/W P/B A/C P/L set up for PTO Locking Front Hubs Locker Rear Axel. Box 14'Long 8' W 7'T with walk ramp. New Tires Cell 20-8582-0833 $17500 or Best Offer
1977 International 1750 4x4
$7,500
This could make a very cool restoration with a matched, period-correct styled camper box. Something like an Airstream Bambi on the back.
http://www.truckpaper.com/listingsdetail/detail.aspx?OHID=3474531&
Ex forest service truck with low miles. Excellent running vehicle with start assist. 4x4. 6 new tires, power brakes, power steering. New HD steel flatbed. 15T Pintle and 2" receiver. New wiring, lights, brakes and exhaust.
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