These are the top 10 most expensive ZIP codes in America. While these ZIP codes represent only a sliver of the U.S. housing market, just 0.1% of all for-sale properties, they highlight where the wealthiest buyers, and their dollars, are concentrated. #1 Most Expensive: At the very top of the list is Miami Beach’s Fisher Island, where the median listing price in July reached $11.9 million. Every home currently for sale here is priced above $1 million, and homes on the market average around 3,835