Why Carl Martens tests ecommerce advice in stores he runs
Carl Martens is CEO of Saints and Sparrows, a Shopify and direct-to-consumer growth agency covering paid media, SEO and AI-search visibility, retention, and Shopify development. Drawing on experience running ecommerce stores, Martens explains how the agency tests its advice, wins clients through referrals, and measures growth against profitable orders.
Judge marketing by profitable orders and repeat customers, not platform-attributed revenue or vanity metrics. Martens argues that advice is more reliable when it has first been tested with real money in a business the team operates.
What’s the short story of how your business started, and what makes it genuinely different from the other options your customers have?
Before I started Saints & Sparrows, I spent seven years building Aventuron, a multi-brand outdoor retailer I founded and grew to more than $50 million in cumulative sales, with $10–12 million a year at its peak. I learned ecommerce the expensive way: my own money on the line for every ad, every email and every site change. When other brands started asking how we did it, I launched Saints & Sparrows in 2026 to bring that operator’s playbook to them.
What makes us different is that I still run stores myself. I co-own NVMOS, an off-road parts store, and run my family’s landscaping company. Every strategy we recommend has been tested in our own businesses first. That’s where we find out what actually moves revenue and what only looks good in a platform dashboard. Clients also get one team across paid media, SEO and AI search, email and SMS, and Shopify development, so nobody is pointing fingers between agencies and every channel is judged against real orders.
How did you win your first customers, and where does most of your new business come from today?
Our first clients came from relationships. I’d spent nearly two decades in ecommerce and B2B sales, so the first brands were people who already knew my work and had watched what I’d built. Early on, referrals did the heavy lifting: one happy client introducing us to a peer they trusted.
Today, referrals are still our best source, but we’ve made a point of marketing the agency the same way we market clients. We run our own paid search, publish content built for both Google and AI answer engines, and show up where business owners are already asking for help: directories, agency roundups and press features like this one. If a tactic isn’t good enough to bring us leads, we don’t sell it to a client.
What’s one decision that changed the direction of your business, and one mistake that taught you the most?
The decision that changed everything was to keep running my own stores instead of becoming a full-time consultant. It would have been easier to stop operating and just advise. But owning real businesses keeps us honest. We feel every wasted ad dollar, and that’s shaped how we work with every client since.
The mistake that taught me the most happened at my own landscaping company. We launched Google Ads the way the platform recommends: Performance Max and broad keywords, letting the algorithm sort it out. Cost per lead was painful. We rebuilt the account so every service had its own campaign, with tight keywords and its own budget, and cost per lead dropped by roughly half. Now every service gets its own campaign, for every client. The lesson: the platform’s default setup is built to spend your budget, not to protect your margin.
What has changed in your industry or in what your customers expect over the last couple of years, and how have you adapted?
Two big shifts. First, how customers find stores. People increasingly ask ChatGPT, Perplexity or Google’s AI Overviews what to buy instead of scrolling search results. Ranking on page one isn’t enough anymore; you need to be the source those engines trust and cite. We’ve built AI-search visibility into every SEO program: clear answers, structured data, consistent brand information across the web, and mentions on sites the engines pull from.
Second, trust in the numbers. Between privacy changes and every ad platform taking credit for the same sale, Meta, Google and email tools can collectively claim more revenue than a store actually made. Clients have gotten skeptical, and they should. So we reconcile everything against real orders and report the honest number, even when it’s less flattering. We’ve also leaned hard into AI tools on our own team, which lets a small agency deliver senior-level strategy and reporting without big-agency overhead.
If you were advising someone starting out in your industry today, what would you tell them to do first, and what would you tell them to ignore?
Do first: sell something yourself. Run a store, even a small one, with your own money. You’ll learn margins, shipping costs, returns and what a customer is actually worth faster than any course can teach you, and you’ll never again recommend a tactic without thinking about whether it makes money.
Ignore: vanity metrics and shiny new channels. Platform-reported ROAS, follower counts and open rates are easy to inflate and easy to brag about. What matters is profitable orders and customers who come back. Every year there’s a new platform or tool everyone says you must be on. Master one or two channels that work for your business before chasing the next one.
Thank you to Carl Martens and the team at Saints and Sparrows for sharing what actually worked with Leaders Perception readers.
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