The complainer has irritated me, but the Landy is not staying to irritate him.  For now I want to hold onto the Landy, until I am in a position (and have a suitable place) to put it back on the road.  With the nature of the vehicle, and the way it is built, using it as a chicken coop will not damage it.  It can be jetwashed out during use as well.  As for the condensation problem, I think I can resolve that by ply-lining, or using that foil-bubble-wrap insulation stuff.
I would like to erect the shed as a coop in addition to the Landy, but I could do without the hassle and expense of a planning application, especially as the land is not residential.
For now, the Landy Coop idea looks positive.  The shed might actually require more effort!  
A legal definition of an accepted animal house would be great, but so far I have not found one.