How to Earn Customers' Trust Your approach to winning new business says a lot about your operation.

As we produced this issue of Entrepreneur, an annoying thing happened: I arrived at work to find my office door closed and locked. Blame the overnight cleaning crew? I don't know — but I never lock my door and don't even have a key, so this was a problem. My colleagues valiantly tried to break in, but it turns out that editors make for bad burglars. Ultimately, I had to find a different way to unlock the door…and in the process, I learned an important lesson about unlocking customers' trust, too.

But first, picture it: There's me, standing around like a doofus, locked out of my own office. At a loss for what to do, I went to Yelp, found a bunch of locksmiths, and emailed them to explain the problem and ask for quotes. Four replied quickly.

The first one simply wrote: "Price estimate: $29." Then, 18 minutes later, they followed up with this promise: "I will give best price."

The second wrote: "$125 to open the door. Just need phone number and address."

Related: Are You Meeting (and Setting) Customers' Expectations?

The third didn't offer a price. "Yes, we can help you," they wrote instead. "Call us to verify your address."

The fourth came from a guy named Jay Sofer, owner of Lockbusters, who wrote me this: "Hi, Jason, thank you for the detail. Would it be possible to send me a quick image of that handle to make certain I give you an accurate quote? Here is my direct email address."

In a matter of minutes, I'd found what feels like a microcosm of business itself. Here we had four competitors. Half competed on price alone. One wanted my business but didn't work for it. And then there was Jay, the only one to address me by name, thank me for my time, or ask for more information.

I sent Jay a photo of the lock. He replied, thanked me again, and explained that the project could cost between $99 and $198, depending on whether they needed to replace the lock's core. A few minutes later, he followed up: "Hi, Jason, some bad news. My technician is at our supplier showing them the image of your lock and we cannot replace that core!" Then he described in detail why the job was complicated and could cost up to $300.

That's a full $271 more than the guy who promised the best price. So of course, I said yes to Jay. When he increased his price up front, he also increased my trust. I knew what I was getting. In contrast, I had no idea what I'd get from his competitors — but I was pretty sure it wouldn't be a $29 bill.

Jay's colleague arrived to do the work, and afterward, I talked to Jay about his business. He's no dummy: He knows how his competitors operate. "Prices and communication are usually vague in an effort to overcomplicate the process," which leads to bait-and-switches, he explained. So in 2008, when he turned to entrepreneurship after losing everything in the recession, he saw an obvious path: "The idea I had starting Lockbusters was to position myself as the good guy," he says. Trust would be his competitive advantage.

Related: 10 Reasons Why Good Customer Service Is Your Most Important Metric

This is smart, but also…isn't it a little crazy? You'd think everyone would do this. How can something so basic — so obvious! — be a competitive advantage? But the truth is, too many businesses treat customers as transactions: They just want to win the business, even if the customer is unhappy as a result. I have theories on why they do this; it could be fear of competition, or just the way they were taught. But ultimately, it comes down to a question of where you find your joy. Are you in business to serve others, or to serve yourself?

Jay knows his answer. "I enjoy helping people and consider it a privilege," he told me. When you think that way, your customer isn't a transaction. It's another person — someone to build a relationship with, even if it's a brief one, and even if it's about something as simple as a lock. Because in any business, in any industry, relationships are what it really comes down to.

So what's the key to unlocking a consumer's trust? It's simple: When you love your work, and you love your customers, you'll do the kinds of things that make people love you back.