The author has included floor plans on several of the vehicles, dividing the book into the categories of buses, small rigs and trucks. According to her, the largest of these motoring homes runs to about 300 sq. ft. and the smallest to about 36 sq. ft. (Lidz 10).
Fantasy bus. Yes. You could say that.
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Lidz, Jane. Rolling Homes: Handmade Houses on Wheels. New York: A & W Visual Library, 1979.