I was 16 when I started reselling online. A few months later, my garage was a warehouse and I was making $25,000 a month.

• Ethan Alexander was a high school sophomore when he started reselling goods on Amazon.
• He did $125,000 in sales last year, before the business became overwhelming.
• He's invested much of the money and plans to use what he learned from the business.

This as-told-to essay is based on a conversation with Ethan Alexander. It has been edited for length and clarity.

Each year, I get a $500 gift from an investment account that my great-grandfather set up for all of his great-grandkids. My gramps — Jack Davis — owned his own company and left a legacy of entrepreneurship in our family.

I get the money on his birthday, May 9th. In 2025, my sophomore year of high school, I came across a video on Instagram about making a profit by reselling items online shortly after I received Gramp's gift. I had stopped playing lacrosse, my typical spring sport, and I was looking for something to fill my time. I used the $500 to pay someone to teach me how to resell.

I didn't do much research, just thought "what's the worst that can happen?" The business took off immediately, and I generated just under $10,000 in revenue that first month. In August, I did more than $25,000 in revenue.

I resold lots of goods at a relatively small profit

Success reselling on Amazon comes from volume. I would find a product where I could make a relatively small profit margin — about $2 to $4 — and sell lots of it. To find these products, I utilized software that many Amazon sellers use. I also used AI to create my own system for finding products.

The first product I sold was laundry detergent, which I could buy at Walmart and resell on Amazon for about a 25% profit. I'd spend hours driving my truck to all the Walmarts in Greater Kansas City, buying as much detergent as I could fit. The garage at my home looked like a warehouse.

After spending afternoons buying the goods, I'd stay up until the early morning packaging them. Then, I'd wake up in the early afternoon and bring my shipments to the post office. Before long, they knew me by name.

I learned about the rewards of business and the risks

The work wasn't glamorous. I was essentially working a warehouse job in my own house. I didn't see much of my friends that summer, because I was focused on scaling my sales.

My mom was a huge asset. She runs her own health and wellness business and is also a business coach. I'm always willing to learn, so I listened to what she told me, and also drew on the skills you learn growing up in an entrepreneurial family.

Still, there were lots of little challenges. I was a minor, and some months I was making $45,000 in purchases. At first, I used my mom's credit card for those transactions, but it kept getting flagged as fraud. Eventually, I had to go to the bank and take out a large amount of cash for my Walmart runs.

I hired a few people to help me pack items, but one of them put the wrong labels on products, a mistake that cost me thousands. I learned about not mixing friendships and business that way. I also had frustrations with the backend of Amazon's seller platforms.

I was making good money and incredibly proud of what I had built — but I also learned a lot about the risks of business, not just the rewards.

I want to own my own business in the future

By February 2026, running the business became overwhelming. My grades were suffering. As a seller, I needed to keep the momentum up to get more sales, so there wasn't really a way to scale back. I decided to stop the business for now.

I spent some of the money on splurges, like clothes and Meta glasses. I've also invested a lot of it.

Now I'm 18, and entering my senior year of high school. I plan to go to college, because I don't see a reason not to — especially since my parents have a college savings account for me. I'm curious, though, whether I'll learn more in business school than I did from running my own business.

I know one thing for certain: I plan to be an entrepreneur. There's no other option, as far as I'm concerned.

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