On this episode of Building Loved Businesses, I had the pleasure of sitting down with Spencer Sierra, the founder and owner of Mainstream Home Improvement in Moline, Illinois. Spencer’s journey from washing dishes in a family restaurant to leading a growing, customer-obsessed company is one of grit, transformation, and purpose.

It All Started in the Kitchen

Spencer’s story began at his aunt and uncle’s restaurant, where he started working as a teenager. He told me how that early experience shaped his worldview. “People just want a good time. They want to relax. They want to improve things in their life. And when you’re in sales, when you’re in service, you’re the bridge between what they’re looking for.” That sense of responsibility to deliver joy stuck with him through every role, eventually steering him into home improvement sales.

While working at a national home improvement company, Spencer realized he could do better by customers. When a colleague floated the idea of starting their own company, he woke up the next morning and said, “Let’s do it.” That moment launched Mainstream in 2001.

What a 20-Year Partnership Taught Him

Spencer was honest about the long partnership that helped launch the company and the difficult decision to move on. COVID exposed cracks in their systems and processes. “We were in business for one or two years, but we just kept repeating that year over and over,” he told me.

When his partner resisted the idea of scaling and systematizing, Spencer realized they had fundamentally different visions. “It felt like a divorce,” he said. And though it was hard, he doesn’t regret moving forward solo. “If people feel like they need a partner to start their own business, they should just work for somebody else.”

Rebuilding the Business Better

Since taking over full ownership, Spencer has rebuilt the business from the ground up. And I could tell he’s proud of how far they’ve come.

One of the first things he did was get serious about financials. “Top line doesn’t pay the bills. Bottom line does,” he told me. He hired a new accountant and bookkeeper, raised prices, and began projecting further into the future.

He also became obsessed with the customer journey. “We just work our way back from that person calling on the phone.” That perspective shift impacted everything from phone scripts to service follow-ups.

And perhaps most importantly, he stopped keeping the vision in his head. “Now we talk about it every day,” he said. Whether it’s in a morning huddle or a monthly meeting, the question is always: How do we make Mr. and Mrs. Jones happy?

Delivering an Experience “Beyond Five Stars”

Spencer has a simple yet powerful company vision: to create experiences for customers that go “beyond five stars.” And his team brings that vision to life in intangible ways. Cookies. Fruit baskets. Local gift cards. Thoughtful check-ins. I loved his explanation: “They hired us to do a service, we’re going to do that service. But we also want to give just a little extra.”

It’s paying off. His team regularly collects glowing Google reviews and gets a steady stream of referrals. “Today we got three Google reviews. I’ll be driving home smiling, thinking about that,” he said.

The Challenge of Implementation

We both laughed about how hard it is to implement ideas when you’re running a business. As entrepreneurs, we get excited by books, podcasts, and conferences, and then reality sets in.

“It’s such a challenge… when you fall in love with an idea, getting everyone else to fall in love with it too,” Spencer said. For him, faith has been the anchor. “I go to the Lord every morning and say, if it’s meant to be, take over. I can’t do this alone.”

He also gave his team a ton of credit. “They know, okay, this guy’s got an idea. Here we go.” It takes patience and persistence, but looking back on the last three years, he said, “I’m overwhelmed at what we’ve been able to do.”

A 15X Vision for the Future

Spencer’s vision is bold: to grow Mainstream by 15 times its current size over the next five years. “There’s a huge need for what we do,” he said. But he knows it’s not guaranteed. “We need better systems. We need the right people. Otherwise, growth becomes chaos.”

When I asked him what he most needed to improve, he said it without hesitation: recruiting talent. “That’s not a particular great skill set that I currently possess,” he admitted. But he’s working on it—and knows the payoff is worth it.

His Best Advice for Future Founders

I closed our conversation by asking Spencer what advice he’d give to someone wanting to build a business they love. His answer was powerful:

“You have to go inward. For me, it’s my faith. I have to look at my weaknesses and work on them. If you don’t do that, you might be okay but not great. Everything else falls into place when you lead yourself first.”

Amen to that. Leadership starts with self-leadership. If you can’t lead yourself, no one else will follow.