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Jim Leach, President
Jim Leach

Jim Leach is a professional engineer with more than 40 years of experience in the design, construction, and development of sustainable housing, cohousing, planned neighborhoods, and urban infill development. The overlapping of these talents is what sets Jim apart from many developers.


Throughout his career, Jim has led the industry in creating green building strategies and community-based housing that combine high-quality design with maximum value. Jim has been a spokesperson for the solar energy movement since the early 1980s and was active in the writing and review of the Boulder Energy Code. In 1997, Jim was inducted into the "Built Green Hall of Fame" by the Home Builders Association of Metropolitan Denver. His award-winning neighborhoods have been recognized by the U.S. Department of Housing and Urban Development, National Association of Home Builders, National Council of the Housing Industry, Urban Land Institute, and The Congress of New Urbanism.


Jim holds a bachelor's degree in architectural engineering and a bachelor's degree in business management from the University of Colorado and a master's degree in construction engineering from Stanford University.

Jim Leach, President
Rosie Sullivan

Rosie Sullivan is the Office Manager for Wonderland Hill Development Company.  Her responsibilities encompass many aspects of our business, including AP/AR, property management, customer service,  maintaining our social media presence, and acting as an interface between community members, builders, and our development office.  Her incredible organization skills keep our team running smoothly.

Raised in Minnesota, Rosie moved to Colorado in the Summer of 2012.  Her first residence in the new state was at Nyland Cohousing.  This is where she fell in love with Cohousing and became fascinated with the concept of intentional living.

You may also recognize Rosie as a staff member for The Cohousing Association of the US where she enjoys closely working with other individuals who are equally excited about advancing the "Cohousing Movement".

After receiving her Associate of Arts Degree from Front Range Community College, she is near completion of obtaining her Bachelor's Degree in Accounting from Metropolitan State University of Denver.

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