The Prodigal Parents by Sinclair Lewis

The autumn, no very great season in the selling of motor cars, had become lively with the sale of trailers in which those citizens of Sachem Falls who had retired from the economic struggle, because they had too much money or too little, planned to go to Florida or California for winter. The Duplex had been booming all summer, but in September, Fred's treacherous rivals, the Conqueror Motor Company, dealt the Duplex a nasty blow with its announcement of the Allover Caravan.

The Allover was not a trailer, but built like a bus, with the motor contained in the body. It burst on Sachem with full-page newspaper advertisements which asserted convincingly that the Allover was easier to drive, easier to park, and much easier to handle in passing other cars. As a minor virtue, in this war of transportation with its almost theological disputation, the Allover's furnishings could readily be removed, turning it into a truck.