The Rockefeller dynasty has lived on the same swath of prime woodland in the lower Hudson Valley for more than a century. In 1983, the descendants of oil baron John D. Rockefeller began to donate what would ultimately amount to more than 1,000 acres of the land to the public, forming the Rockefeller State Park Preserve. At the same time, they created an enclave around the new park where they could live in virtual solitude. Asked what happened to Abeyton Lodge, the historic home he grew up visiting on the estate, David Rockefeller told The New York Times in 2002 that when no relatives chose to live in it, it was leveled to ensure privacy: “We really wouldn’t have wanted non-family members living inside the fence,” he said.

Fast forward to the present day, and that’s exactly where Linda Gaunt and her husband, David Packer, are living—inside the fence. Their property, and the 3,700-square-foot prefab that rests on it, is right next to David Rockefeller’s Georgian mansion. What is it like living down the road from the scion of one of America’s most famous fortunes? No complaints. The 101-year-old philanthropist, the only surviving grandson of John D. Rockefeller, has softened his stance lately on living among outsiders. Linda observes, “The only time we’re even aware that we have a neighbor is when his helicopter flies by or we see him being driven around in a horse-drawn carriage.”

David and Linda, who run a PR firm in Manhattan, purchased the 4.6-acre parcel from a business associate of the Rockefellers. Knowing that buildable lots in the area, located just 40 minutes from Grand Central by train, are rare, the couple seized the opportunity.

The next step was choosing a home. David and Linda were attracted to prefab for its easily predictable costs, and paid multiple visits to a Breezehouse model in Copake, New York, that they ultimately decided to buy. The ranch-style house was designed by Michelle Kaufmann in 2005 and sold to Blu Homes in 2009 when her company closed as a result of the mortgage crisis. The prefab maker continued to update its basic design, which features an open floor plan and butterfly roofline. Sixteen-foot-wide sliding glass doors flank the ends of the primary living space, perfect for framing views.

Working at home allowed David to assume the duties of general contractor. “It was a tremendous undertaking, with very little guidance from anyone,” he admits. “I lost a lot of hair but also saved a lot of money.” By dealing with tedious yet vital details like organizing building permits, inspections, subcontractors, and land development, he trimmed $250,000 from the project budget. The final cost was approximately $325 per square foot. Even more satisfying, the couple were able to deviate from the Breezehouse template and put their own stamp on the house: The front door was relocated to gain extra space in a guest bedroom; in the master suite, closets were expanded and several windows were removed (for sleeping in on weekends); and a gas fireplace was replaced with a sleek wood-burning model by Stûv. The biggest tweak was the addition of a site-built mudroom, which connects the gym/office, the garage, and the rest of the house.

The time from factory production to delivery was four months. Each module, transported cross-country by truck, was hoisted onto the foundation by crane. For the owners, watching the flat-pack “pods” unfold like giant origami cubes is the kind of instant gratification that isn’t possible with a site-built house. Having them pre-assembled in Blu’s climate-controlled factory in Vallejo, California, was also a bonus, resulting in tight joint fits that slash energy costs. Compared to the residents’ previous home, a 5,000-square-foot midcentury relic riddled with gaps and drafts, the prefab is a green machine. Energy bills are now one-sixth of what the couple were accustomed to paying.

“Before buying here, we spent eighteen months house-hunting and didn’t find anything we liked,” says Linda. “Every listing we walked through felt like somebody else’s home.” David nods in agreement. “It’s so different living in a place you had a hand in building. It’s a very satisfying feeling.”

With ample room for three children who visit on holidays, as well as two rambunctious dogs—and no stairs to climb—this house fits the couple like a glove. Throw in 45 miles of trails winding through a pristine state park, and you have the kind of idyllic bliss that even jaded New Yorkers can appreciate.