In the 1930s, Sarasota was buzzing with circus stars, Gilded Age money, and Mediterranean Revival mansions springing up along its waterfront. One of the finest survivors of that era, Casa del Carnevale — a nationally registered historic estate with roots in John Ringling’s glittering circle — has just hit the market for $17.5 million. Built in 1936 for industrialist Charles E. Leigh, co-founder of...