Owners of the Vashon Health Center and Allstar Fitness, a Seattle-based athletic club, have signed letters saying they’re interested in moving into K2 Commons, should the ambitious development plans a mile south of town come to fruition.

The letters mark the first significant milestones since Islanders Dick Sontgerath and Truman O’Brien announced their far-reaching plans last December to renovate the largest commercial structure on the Island and develop it into a complex of nonprofit and for-profit enterprises. They’ve also received letters of intent from well-known artists Bo Bartlett and Betsy Eby, from long-time Island architect Keith Putnam and from South Seattle Community College, which would like to offer continuing education courses in cooking and nutrition at the site.

In a related move, Sontgerath and O’Brien say they hope to sign a purchase and sale agreement for the 19-acre site this week. While the exact price was not disclosed, parties on both sides said the price was close to $5 million. The deal requires that they close on the real estate transaction by the end of this year.

Sontgerath and O’Brien have also changed the business model: They’re now planning to pull together a consortium of investors to purchase the building and develop it; tenants will then lease space. Under their previous plan, tenants — or investors acting on their behalf — would have been required to own their portion of the building, a condominium-style development.

The two men said the letters of intent, particularly the one from Allstar Fitness, are coups for the project. Since the get-go, Sontgerath said, he has envisioned a development that featured an athletic facility that also serves as a kind of community center for Vashon. Bob Padgett, the owner of Allstar Fitness, shares this vision, Sontgerath said.

“The heart and soul of the project are now in place,” he said.

Under preliminary plans, the 44,000-square-foot fitness center — similar to a $17 million project Allstar built in Tacoma — would include lap and family swim pools, state-of-the-art cardio equipment and machines, sauna and steam rooms, an on-site day care for those using the facilities and a large lobby that would act as a lounge, or as Sontgerath puts it, “the community’s living room.” Allstar would also run an adjacent 10,000-square-foot space that would be a tennis court by day and an events center by night — hosting gatherings such as the recent PTSA auction and sock hop that were held at K2.

The plans call for investors, including Sontgerath’s own company, The Heritage Group, to provide “a majority of the capital” for the development of the athletic facility, he said, sharing in the profits proportionately. Allstar would also invest in the development of the facility as well as operate it, he said.

“We consider Allstar’s participation in the project a given,” Sontgerath said.

An eight-lane bowling alley and cafe that would serve the entire complex are also built into the development costs that Sontgerath will present to potential investors, he said. The team is currently looking for a management group to run the bowling alley; Sontgerath has already found an owner/operator to run the cafe, a name he’ll announce soon, he said.

“We responded to two things we kept hearing from the community — their desire for both a swimming pool and a bowling alley,” Sontgerath said. “As the design evolved, we realized there was a space that was perfect for a bowling alley. So we took the plunge and built the cost into our capital budget.”

But Kevin Allman, who owns the Vashon Athletic Club across the road from the K2 complex, said he doubts the Island could support both Allstar and his facility, which has a small pool. Allman, who has had several discussions with Sontgerath and O’Brien about the development, said the three men have decided that if an athletic club becomes a part of K2 Commons, Sontgerath and O’Brien would buy him out.

“I’m a reasonable enough business owner that I’m open to that,” Allman said. “Based on what their goals and intentions are, I think it would be difficult for two facilities to co-exist. … I could make it difficult for them. But in the long run, it’s probably in my best interest to sell it if that becomes necessary.”

Allman, however, said he’s doubtful the Island’s big enough to sustain a large athletic club like Allstar. He’s currently renovating the women’s locker room and said he plans to continue to move forward on his own plans for the ongoing development of his club.

“It could happen,” he said of Allstar. “But we’re doing fine.”

Under the commitments Sontgerath and O’Brien have secured, around 60,000 square feet of the project — or nearly half of its usable space — has been reserved by potential tenants. After Allstar, the next largest space that a potential tenant has spoken for is the 11,000-square-feet portion for the Vashon Health Center. Bartlett and Eby, the artists, have asked for a “big loft,” a 4,000-square-foot space; and architect Putnam would lease a “baby loft,” which is 1,000 square feet.

The King County Library System, meanwhile, is still considering a separate building on the site, the 10,000-square-foot former machine shop. Kay Johnson, the library system’s director of facilities, said the administration would move forward “if we found a satisfactory arrangement with the K2 group.”

“We’re still interested, but we just haven’t decided yet,” she said. “It’s pretty much a real estate decision at this point.”

Should the health center move into K2, it would occupy the section of the building just to the north of its main front door, on the Vashon Highway side. Bert Colburn, administrator of the Highline Medical Group, which manages the Vashon Health Center, said he decided to sign the letter of intent after a “town hall” style meeting with the health center staff a few weeks ago. The staff has long needed and wanted a new space, he said; the current facility is large enough but configured poorly for the demands of a medical practice.

But Highline is also considering the possibility of a new facility at the Sunrise Ridge site, where it is currently located. Sunrise Ridge Health Services, the nonprofit organization that owns the property and facilities at the xx-acre site xx miles south of town, is putting together a proposal for a new health center building at Sunrise Ridge. The group hopes to have a proposal by September, Colburn said.

Once both proposals are before it, the Highline Medical Group will decide what’s best for the Vashon community and the health center, Colburn said.

The health center would lease the K2 space for $9.26 per square foot a year, which Colburn called “a good rate.” The organization, like all the tenants, would also have to pay some management fees, he said; the Heritage Group, meanwhile, would take on what’s called “tenant improvements,” creating the infrastructure the health center would need to make the space work.

“This is a nonbinding letter of intent, but we felt we wanted to at least throw our hat into the ring,” Colburn said.

But even with tenant improvements, the health center would have to invest $600,000 to $800,000 to fully develop a new K2 healthcare facility, Colburn said. Building a new structure at Sunrise Ridge could likely cost that much, as well.

The community, he said, “needs a modern health care facility. … We’re just going to have to wait until September and see what we have. And then we have to get serious about some grant dollars and hopefully get some money from the Highline (construction budget) … and get this thing done.”

As for South Seattle Community College, it hopes to offer non-credit culinary courses in a commercial kitchen that Sontgerath and O’Brien plan to build in the new complex. The two men have met several times with Jill Wakefield, the president of the community college, as well as top administrators.

“We have a shared vision as to the tremendous potential for food and wine education at K2 Commons,” O’Brien said.

Gary Oertli, interim vice president for instruction, said that Vashon is part of the community college’s service area and that it thus made sense for the school to consider offering some classes; its food and wine courses, he added, are particularly popular. Sontgerath and O’Brien are asking for “a nominal rental fee” for the community college’s use of the commercial kitchen, once it’s built, he said.

If the college finds that there’s more demand for its services on Vashon, including for-credit classes, it will respond accordingly, he said.

“It’ll be based on consumer demand. … This is a toe in the water to see if there’s an interest in continuing education classes on Vashon,” Oertli said.

Sontgerath and O’Brien said they’re thrilled to have these letters of intent in hand and are particularly excited about the partnership with Allstar Fitness. During a visit to its Tacoma site with a reporter last week, the two men pointed out several of the facility’s features — from a basketball court to state-of-the-art cardiovascular machines to a teen center. They toured the swimming area, a so-called “waveless pool” with seven lanes for lap swimming as well as a children’s area where the sides of the pool gradually slip into the water, pointed out the dry and steam saunas and entered the drop-in child care facility, where a group of kids were playing with two adults.

A three-story tall climbing rock marked the front entrance of the 70,000-square-foot facility; nearby, several couches were arranged in front of large television screens built into the walls.

“It’s so much more than a club,” Sontgerath said as he stood in the middle of the brightly lit lounge area. “It’s a living room and a kitchen.”

The K2 facility would be smaller than the Tacoma one, but similar in many respects, the two men said. “Can you imagine this on Vashon?” O’Brien asked.

The costs for joining Allstar vary site to site, and, like many clubs, it offers special rates and deals at different times of the year. The current fee is $75 to join and $39 a month for one adult; other family members age 14 and up are another $29; kids 13 and under are free. Sontgerath and O’Brien said they plan to make sure the Vashon club would include scholarships to make it affordable to lower-income families.

“We want to make the health club accessible to everyone on the Island,” O’Brien said.

David Hackett, who chairs the Vashon Park District board, said a swimming pool in a private club might be the only way to get a good-sized pool onto the Island. People have talked for years about covering the outdoor pool operated by King County, but the effort has never gotten far, he said.

“The devil’s in the detail. It always is,” he said of Sontgerath and O’Brien’s effort. “But it sounds like it’s something worth watching and see how it turns out. We don’t have any public entities taking on something like this.”

Plans include a health club and a bowling alley