Complex sentence: In 1902 they designed Flagler's own estate, Whitehall, in his resort of Palm Beach, Florida, an Italianate villa faced with white stucco, with palatial interiors in "Louis" styles ranged round an entrance hall with double staircase.
Split into simpler sentences: In 1902 they designed Flagler's own estate, Whitehall, in the resort he developed, Palm Beach, Florida. Whitehall is an Italianate villa faced with white stucco, with palatial interiors in "Louis" styles ranged round a grand entrance hall with double staircase.