Billionaire Facebook founder Mark Zuckerberg and wife Priscilla Chan have been vacationing in Hawaii, and taking some time to search for property on the islands. The low-key couple, worth $13 billion, were spotted embarking on a helicopter tour with a real estate agent to view property and land in Kauai. Zuckerberg, in shorts and a T-shirt, and Chan were later spotted dining at a casual burger restaurant. In April this year the couple vacationed on Kauai and were seen dining at picnic tables at local favorite Bubba Burgers. Months earlier they had visited Maui. Chan told The New Yorker, “We try to stick pretty close to what our goals are and what we believe and what we enjoy doing in life — just simple things.”