A luxury property listed for $13.9 million on a 22-acre island sold on Friday, completing the highest private real estate transaction on Flathead Lake.

Dawn Maddux, the listing agent with Engel & Volkers Western Frontier’s office in Missoula, said the buyer wants to remain anonymous, though she said he has properties around the world.

The final selling price wasn't publicly disclosed.

“I represented the buyer and the seller, so it was a little difficult and complicated, but it worked out and everyone is happy,” Maddux said Monday morning. “One of the biggest challenges is there's just not that many buyers. It's a very limited buyer pool.”

The 22,000-square-foot home has appeared in global real estate brochures, including frequent listings in the Wall Street Journal. The residence is spread across three levels accessed by an elevator, while the great room offers 45-foot ceilings.

The home includes eight bathrooms, a copper conservatory, an observatory with views of Flathead Lake, and an office lined with mahogany, among other luxury amenities.

“It definitely took the right buyer who appreciated the level of quality, the finishes and construction,” Maddux said. “It was on the market with me coming up on three years. That was with this seller.”

A year ago, the property was listed for $22.7 million and its sale completes one of the highest private real estate transactions in western Montana in recent times – and the highest ever on Flathead Lake.

Maddux is also the listing agent for the $27.5 million Hampton Trail home in Hamilton and the $13.9 million Bearmouth Legacy Ranch. She's also the agent for Marshall Mountain, a former ski hill and lodge currently listed for $2.5 million on Marshall Canyon Road outside Missoula.

“I've always focused on the luxury sector of the market,” Maddux said. “I knew getting in that I had to go find buyers. The days of putting it on the (Multiple Listing Service) and waiting for people to call are over.”

Maddux, who worked at Glacier Sotheby’s prior to opening Engel & Völkers Western Frontier last year, said that while selling a multimillion dollar home in Montana takes time, the properties are beginning to move.

But selling luxury homes priced valued at tens of millions of dollars, such as Flathead’s Shelter Island, can be unsettling. Doing so doesn't come cheap, given the high-end marketing that's required and the need to reach a global audience.

“I probably spent over $50,000 marketing this property,” Maddux said. “It's a big risk when you take them. You could spend $50,000 and lose the listing. But you have to be willing to take that risk and plow forward with confidence.”

Montana remains a nondisclosure state, so the final selling price of its high-end properties isn't often revealed. Neither are the buyers who make such purchases.

“They just have a really high net worth,” Maddux said of her luxury buyers. “Montana has a special allure. We're sparsely populated, it's very private, and our community is very unobtrusive. Even someone famous, when they're here they don't get bothered.”