Owner-led · Stillwater, Oklahoma

Building companies.Creating opportunities.Leaving a legacy.

Legacy Built Holdings is Colin Plant’s owner-led holding company. We bring together business interests and brands with a shared focus on useful work, strong teams, and long-term value.

Explore our businesses Contact Colin

Operate with discipline.
Build for the long term.

Our businesses & brands

Distinct purposes.
Shared standards.

From home comfort to apparel, creative work, and founder-led media, each serves its own audience. Explore the business directly or contact Colin to start a conversation.

HVAC · Service · New construction

OnSite Heat & Air

Heating and cooling service, replacement, maintenance, and HVAC for new construction, serving Stillwater and surrounding Oklahoma communities.

Visit OnSite

Company Recognition & Credentials

2025
Oklahoma Innovation Expansion Program — Award Recipient (opens in a new tab) OnSite Heat & Air was listed as a $25,000 award recipient through the Oklahoma Department of Commerce's Innovation Expansion Program, a state business expansion incentive. 2025 award recipients (XLSX) (opens in a new tab)
Dealer
Lennox Premier Dealer (opens in a new tab) Recognized as a Lennox Premier Dealer, reflecting high standards in service, professionalism, and customer satisfaction.
BBB
Better Business Bureau — A+ Accredited Business (opens in a new tab) OnSite Heat & Air is a BBB Accredited Business with an A+ rating.

Company distinctions are separate from Colin Plant's personal recognitions. Ratings and dealer designations can change over time.

Apparel · Lifestyle

Hard Earned Apparel Co.

Apparel and goods rooted in hard work, discipline, and family. Built for the life you earn.

Shop Hard Earned

Personal brand · Entrepreneurship

Colin Plant Survive + Thrive

Real-world perspectives on entrepreneurship, leadership, family, and building a meaningful life. Survive the chaos. Thrive on purpose.

Follow Colin on Facebook

Why Legacy Built exists

Build what matters.
Leave it better.

Legacy Built connects Colin’s business interests, brands, and long-term ambitions under one ownership identity.

Our focus is strengthening the people, systems, and brands behind useful businesses. We value steady improvement and opportunities that can grow beyond one person’s daily involvement.

Useful work

Solve real needs and stand behind the work.

Strong teams

Build clear roles, capable leaders, and room for people to grow.

Lasting value

Make decisions with the next chapter in mind.

Leadership

Colin Plant

Founder & CEO

Colin is an Oklahoma entrepreneur and business operator whose work spans residential HVAC and new construction, brand development, and media.

His focus is building capable teams, clear systems, and businesses that serve their communities well. Legacy Built brings those interests together with a long-term view of ownership and opportunity.

Founder profile

Recognition & Industry Features

2025
Entrepreneur of Impact — Quarterfinalist (opens in a new tab) Colin Plant advanced to the Quarterfinals of the 2025 Entrepreneur of Impact competition.
2022
ACHR NEWS — Best Contractors to Work For (opens in a new tab) Featured in the February 2023 edition of The ACHR NEWS alongside Jeremy Dye as part of the leadership team at Integrity Heat & Air in Guthrie, Oklahoma, a 2022 Best Contractors to Work For honoree.

Our long-term standard

Build businesses that create opportunity today and value for the next generation.

Start a conversation

Built on good
relationships.

For business partnerships, brand projects, or media collaborations, send Colin a short note.

colin@legacybuiltholdings.com

Need heating or cooling service? Contact OnSite directly (opens in a new tab).

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Your information is used to respond to your inquiry. Privacy & inquiries.

Privacy & inquiries

Legacy Built Holdings uses the name, email address, inquiry type, and message you provide to respond to your inquiry and manage the resulting conversation. Submitting an inquiry does not subscribe you to a marketing list.

The inquiry form is provided by Jotform, which processes and stores form submissions on our behalf and may use cookies or security checks needed to operate the form. See Jotform’s privacy policy (opens in a new tab). External business and social-media sites have their own privacy practices.

Share only information relevant to your inquiry. For questions about a message you have submitted or a request to delete it, email colin@legacybuiltholdings.com.