 His development projects built several new communities, including Hesperia and Salton City in California, and Christmas Valley in Oregon.In 1923, Phillips opened the new subdivision of Clear Lake Highlands near Clear Lake, California which, in 1980, became part of newly incorporated Clearlake.In 1955, he was president of Hesperia Land Development and Hesperia Sales Corporation, while conceiving the "U-Finish Home", mass-produced housing units that were completely finished on the outside leaving the buyer to complete the interior.