Former “This Old House’’ host Bob Vila is selling his place on Martha’s Vineyard, and, trust us, the new owner won’t need a home-improvement expert like Vila. They will, however, need a lot of money because the house on Quitsa Pond in Chilmark is listed for $15.9 million. The estate, dubbed “Skymark,’’ includes two houses with seven bedrooms, six bathrooms, elaborate gardens, a dock, a pool with spa and waterfall, and panoramic views over Quitsa and Menemsha ponds, Vineyard Sound, and the Elizabeth islands. We don’t know why Vila would want to part with such a beautiful property, but there has been some drama in the neighborhood related to an enormous house nearby. Adam Zoia, founder of the executive head-hunting firm Glocap Search, built a mansion whose size, some neighbors complain, violates town zoning laws. Clam Point Cove, where Zoia’s and Vila’s houses are located, is also where Laurie David, ex-wife of comedian Larry David, lives.