Thanks for the replies.
It would certainly be interesting to see how far I could go with buying/using things in the name of the croft business. I wouldn't want to be doing anything dodgy of course, but the idea of buying things like trailers, ATV, fencing etc VAT free is very appealing.
Has anybody had any difficulties with things not being accepted as legitimate business expenses? Or does your accountant stop these before they become issues? Thinking, for example, about buying a small van which would be both a business and personal vehicle.