Seems to me that 'Old Blue' could make a perfect 'man/woman' cave. I can easily figure out semi-permanent hookups for electric and water and sewage. But heating and cooling are the question. 'Old Blue' sits in a garage all year 'round. Running the propane heater inside a closed garage in the winter does not seem like a good idea. But I could probably use a properly sized ceramic heater for that purpose. But cooling is a different thing. The inside air temp in the garage in the summer is about 10/15 degrees warmer than the outdoor temp and it seems using hot air for the roof mounted air conditioners is not a good idea. Maybe there's some kind of a machine that I could put in the Barth that heats and cools? I've looked at the portable units but the ones I've seen require ducts to bring air in and take air out. Maybe a small heat pump outdoors that I could run some kind of a duct from? Hey, if you're not going to run it on the road, you might as well get some use out of it.
Jim

Or put a roof vent in the garage to evacuate the hot air. Then install a swamp cooler (oops. wrong part of the country).

A high mounted exhaust fan and a low-mounted intake fan would circulate enough air to rid the barn of the temp differential, and to clear the furnace exhaust in the winter.

Here's an idea: http://en.wikipedia.org/wiki/Solar_chimney

Some form of this system might work for you. Truck stop no idle