A 6-inch Chinese porcelain bowl that was bought for $35 at a Connecticut yard sale was sold at auction Wednesday for a staggering $721,800, which includes a buyer’s premium. It was expected to fetch between $300,000 and $500,000 at Sotheby’s on the Upper East Side. The hammer price, which does not include the buyer’s premium and overhead premium, was $580,000. The name of the winning bidder in the Sotheby’s Auction of Important Chinese Art auction is private.