A Maui woman who once lived out of a van and took showers at the beach has sold a majority stake in her 7-year-old baby carrier business for $91 million.

Karin Frost, owner of Pukalani-based ERGObaby Carrier Inc., agreed to sell 84 percent of the company she started in her home to a Connecticut firm that invests in businesses with attractive growth prospects.

Compass Diversified Holdings said it is paying $91 million for the controlling stake, including cash and Compass stock plus the assumption of ERGObaby debt. The Compass stock compensation is worth $6.9 million. The cash and debt figures weren’t disclosed.

Frost and other investors still own 16 percent of ERGObaby.

Frost, 49, founded the company on Maui in 2003 to make wearable baby carriers after one she made one for herself as a new mom in 2002 caught on with friends.

Frost set up manufacturing in China, and hit it big in 2007 when the 20th anniversary issue of Parenting Magazine named the ERGObaby carrier one of its Top 20 products in the past 20 years.

Last year, ERGObaby had sales of $22.8 million from its line of carriers and other products including bags, changing pads and bibs through 700 retailers and online sites in about 20 countries. ERGObaby carriers sell online for $105 to $148.

Some observers of the Compass deal were awestruck by the purchase price. A price double or triple annual sales is often a typical for a privately owned merchandise business, but Compass is paying close to five times annual sales.

ERGObaby employees said Frost was traveling yesterday and unavailable for comment.

In a statement prepared by Compass, Frost said Compass provided exciting opportunities to further expand ERGObaby.

Jeff Henderson, a friend who owns sail manufacturing firm Hot Sails Maui and helped Frost perfect her baby carrier through a Chinese factory, said he was pretty "blown away" three years ago when ERGObaby was selling about 10,000 carriers a month. Yesterday, Henderson was stunned again over just how much Compass is paying for control of Frost’s company.

"No way," he said. "That is just wild. I’m happy for Karin."

In a 2007 Honolulu Advertiser story, Frost said she never imagined that her homemade baby carrier would lead to a successful multimillion-dollar enterprise.

"Oh my god," she said at the time. "This company is just beyond my wildest dreams."

According to the story, Frost moved from Wisconsin to Maui in the mid-1990s, and took on a free-spirited lifestyle working odd jobs, living in a Volkswagen van and showering at the beach. "Just kind of juggled life," she said.

Frost moved back to Wisconsin, but decided to sell her home there and returned to Maui in 1997. This time, Frost, who had a master’s degree in clothing design, took an entrepreneurial path and designed two lines of clothing. The venture failed.

In 2001, Frost had a son, Keala Kaj, with her partner, Lee Lopez. Then 41, Frost was disappointed with baby slings and pouches on the market. She sought one that was comfortable and would keep her son as close to her body as possible.

Close contact supports an idea made popular by author Jean Liedloff called the "Continuum Concept" that says a mother needs to keep her baby as close to her body as possible for optimal early child development.

The baby carrier Frost designed also allows the bulk of a baby’s weight to sit on a mother’s hips — not the spine.

Compass called Frost an "industry pioneer," and said her business was attractive because of its strong brand recognition and demand among a passionate and loyal customer base.

Compass plans to work with Frost to expand product offerings and distribution, and envisions that the company will benefit from increasing births worldwide, rising affluence in non-Western markets and growing popularity of wearable baby carriers.

"ERGObaby is an exciting company for us to acquire," Joe Massoud, chief executive officer of Compass, said in a statement.

Compass is a publicly traded company formed in 2005 to acquire controlling interests in profitable small to middle-market businesses with strong management in attractive niche industries.

The firm owns majority stakes in seven other companies besides ERGObaby, including a maker of home and gun safes acquired in April for about $70 million, a maker of high-end suspension products for off-road vehicles acquired in 2008 for $85 million and a temporary staffing services company acquired in 2006 for $128 million.

Other Compass subsidiaries are engaged in making circuit boards, furniture, medical devices and brand promotion items.