Adam and Brenda Elberg of Melville, N.Y., are not planning to move to nearby Dix Hills until later this year — their new house there is still under construction. But they’ve already “gotten to know some of the other people moving in” to their new neighborhood, Mr. Elberg said, meeting them during visits to the building site.

Now he sees his future neighbors at school functions — the blue-ribbon Half Hollow Hills Central School District serves Melville and Dix Hills as well as a number of other communities. “They are all young families with kids,” said Mr. Elberg, 46, a father of four and an owner of Professional Physical Therapy, a chain of 63 offices.

The Elbergs are among the first 10 buyers at Oak Hill Estates, a development of 23 houses, starting at nearly $2 million, being built on one-acre lots on the former Dix Hills Golf Club public course. The Elbergs’ six-bedroom five-and-a-half-bath house cost $2.24 million, not including upgrades.