This tradition of small, nearly identical row houses reached its apex with a series of developments begun in the 1920s. Over the course of a few decades, several builders, including Carl and Fred Gellert, R.F. Galli, Oliver Rousseau and, most famously, Henry Doelger, converted the area's still vast sand dunes to a residential neighbourhood with the construction of thousands of new homes. Doelger's development was by far the most massive: between the late 1920s and mid-1940s, his company erected an estimated 11,000 homes in the city; from 1934 to 1941, he was the most prolific home builder in the country. Doelger houses were an early example of assembly-line building on small lots, yielding affordable, well-crafted, single-family homes designed to meet Federal Housing Administration standards. Though the façades vary, borrowing traces of Spanish and American colonial, French provincial or modernist traditions, they are united in appearance by their stucco exteriors, equal size and a consistent layout that features bay or picture windows over the centrally placed garage. Just as in post-war suburbia, model homes were built to solicit buyers. Doelger occasionally marketed these sites with contests, such as a 1942 promotion that linked domestic consumerism with patriotic duty: participants were instructed to visit the 'Freedom House' and submit their response to the prompt 'I am glad to be an American because…' for the chance to win $75 in US defence bonds. Moreover, such suburban resonances were not simply a matter of architectural appearance or the common equation of home purchases with nationalist pride; both Doelger and the Gellert brothers' Standard Building company included racial covenants in their property deeds, resulting in a population that was, like much of post-war suburbia, overwhelmingly white.