Beth de Groen, a well-known real estate agent on Vashon, and her husband John de Groen have bought Vashon’s Windermere office from long-time owners Dick and Linda Bianchi.

The de Groens signed papers for the transaction Tuesday and publicly announced the purchase Wednesday. Beth de Groen, who has been an agent on Vashon since 1993, is leaving John L. Scott’s Vashon office to take on the new role.

“It was very difficult for me to make this decision,” said de Groen, who has worked for Ken Zaglin at John L. Scott since 2000. She said she wept when she told him.

But the opportunity to manage a real estate office after years of working as an agent was too good to pass up, she said during an interview at the Windermere office with both Dick Bianchi and her husband John at her side. And at age 63, she added, she realized that if she were going to make such a move, now was the time to do it.

“There aren’t many games in town,” she said, referring to Vashon’s real estate world. “It just seemed if I wanted to become a manager, this was my opportunity. …. It’s a much more varied job.”

The move brings her full-circle, she added; she worked for Windermere for her first seven years as an agent. “So I’m coming back,” she said.

Dick Bianchi, 67, said he decided it was time to consider selling the firm he and Linda bought in 1997 after two years of serious health issues. In November, after he had surgery for a benign brain tumor, he told his agents at Windermere that he was ready to begin entertaining offers to purchase the business, he said.

“Somewhere along the line, Beth heard about it and gave us a call,” he said.

The Bianchis, however, aren’t walking away from the real estate business. Linda will continue to work at Windermere as a real estate agent. And Dick, a licensed agent who has not actively sold in his capacity as the firm’s owner, said he will help his wife or Beth, as needed; he might also go into commercial real estate, he said.

John de Groen said he’ll use his financial and technical background to support the firm. “I’ll fill in the holes,” he said.

The move is a significant one in Vashon’s small but intense world of real estate. Beth de Groen has long been John L. Scott’s most productive agent, helping the firm achieve the lion’s share of the market on Vashon.

Though both offices have about the same number of agents, John L. Scott’s Vashon office handled 42.7 percent of the units sold last year, amounting to 44.5 percent of the market in terms of dollars, statistics show. Windermere, the second busiest office on Vashon, had 20.5 percent of the sales and a market share, in terms of dollars, of 23.6 percent.

Zaglin, reached Thursday, said he was sorry to see de Groen leave his office but also understood fully her desire to take on new responsibilities and challenges.

“It’s exciting news for her. I have nothing but good wishes,” he said.

He also said he doesn’t believe it will amount to a significant change for John L. Scott.

“The shift of a single agent isn’t going to dramatically affect us,” he said. “The market is tight. … But our head is certainly above water. … We’re going to miss Beth. But we’re going to continue to see her.”

The de Groens’ daughter Sophia de Groen, also an agent, will continue to work for John L. Scott.

The sale does not include the Bianchis’ commercial real estate holdings, a five-acre parcel with two buildings — including Windermere’s current office — which they own with other business partners. It also does not include the property management business operated by a Windermere agent.

Beth and John de Groen, meanwhile, say they plan to run the business much the way the Bianchis have. Denise Katz, a well-known agent at Windermere, will continue to work as the firm’s sales manager, for instance.

“The people who work here are great. That goes for clerical staff as well as agents, and I don’t see any reason to change that,” Beth de Groen said.

She doesn’t see a need to expand Windermere’s market share, she added.

“I want to have a well-organized, happy group of people serving the Island’s needs and keep the doors open. I just want to have a viable business,” she said.