About Our Team

Dan Siddall

Broker & Owner


40 Years in Boulder County


34 Years Connecting Sellers and Buyers


22 Years living in Lyons, Colorado


Forever in the band


Dan Siddall understands every aspect of our local market and the dynamic diversity of home sellers and buyers. That is why 90% of Dan’s success comes from personal referrals.


Raising a little boy and running a yoga practice takes all my time.  When I had the opportunity to finally buy my son and I a home the idea was scary.  Colleen took all the pressure off, negotiated with the seller and closed the deal for me.  Years later and we’re still in the same home in a thriving community.  Thanks Colleen!


Jane Janie

Yoga Instructor, Single Mama

John Hyman

Associate Broker

I became a real estate agent in my senior year at U.C. Berkeley, while majoring in Econ. As I went through great old Berkeley and Oakland houses and their forlorn gardens, I found I could see them already fixed up and proud in a variety of new ways and styles. This led me to later work for many years as a landscaper with my wife and partner while we raised two kids, remodeled two homes, and designed and installed hundreds of beautiful projects to be proud of. Listening closely and designing to the particular style, tastes and needs of the clients was our forte. Here in Lyons my imagination fills to overflowing at the possibilities for great projects in so many homes and properties I see. I like to listen closely and match my people to their next home, help them get it, and see them beam and smile when the changes they make to the house make them feel proud. I am in my element.





Windu and Zoe

Welcome Waggin’ Ambassadors

Come by and meet our furry team members and Gateway Realty Ambassadors, Windu and Zoe. They are at our 324 Main Street office several days a week for a friendly welcome and free love.




“Thanks so much to Dan Siddall for a wonderful home selling experience! We vastly appreciate his extensive knowledge of
the Lyons/Boulder County area real estate market as well as strong communication and negotiation skills involving buyers and sellers.
Dan made the process of selling our home so much easier through his ability to answer all our questions, come up with the perfect game plan with regards to marketing and staging our home, and being diligent and persistent with helping us find the perfect buyer.
We highly recommend Dan to anyone looking for a very personable and highly skilled realtor in the Lyons/Boulder/Longmont area.
Best realtor in Boulder County!”
Greg and Anne Berman

Hall of Fame

Lifetime Achievment Award

Selling Your Home Fast

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Colleen Dickes

Associate Broker

Colleen is in her 6th year working for Dan and received her license in 2014.  While they are now business partners, most know them as the father/daughter duo that has been in Lyons since 1995.  Colleen plays a key role at Gateway Realty in all transactions by assisting Dan and the Gateway Realty team. She is innovative and implements efficient systems while being highly organized and task orientated. As a mom to two young children, Colleen is compassionate and understanding of the needs of families looking to move in and around the Lyons area. Colleen is also a buyer specialist and is ready to help you find the perfect home.





Seth Portner

Associate Broker

I am a 25 year resident of Boulder County having found paradise in Lyons, CO.  Several times an entrepreneur,  most recently in the field of residential energy efficiency and utility energy conservation, I have turned my focus towards my long-term interest in real estate, both for investment and housing.  My goal is to work with just a few people per year that are interested in the Lyons, CO area to make their new home, or to make a real estate investment- and to share my accumulated knowledge of real estate and business to help you accomplish your goals.  I am affiliated with Gateway Realty, a local Lyons, CO real estate firm, and am a licensed Colorado Real Estate Broker, Realtor, and hold a M.S. from the University of Colorado Business School. View my website here.




Whether a Seller, Buyer or Both -we've got you covered

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