3 Stocks That Turned $7,000 Into $55,000

When someone tells me about a stock that's a great buy -- one that doubled or tripled in value over the last few years -- I assume it's some hot tech start-up.

But juicy returns don't necessarily come from just young, risky, untested companies. And they also don't need to come from the tech sector. Here are three companies from non-tech industries -- trucks, airlines, and uniform rental -- that have turned $7,000 into $55,000 or more in less than 10 years.

The best part is that they may still have room to run. Here's how Oshkosh Corporation (NYSE: OSK), Southwest Airlines (NYSE: LUV), and Cintas (NASDAQ: CTAS) are keeping the good times rolling for their investors.

An oldie but goodie

The oldest company on the list, Oshkosh Corporation, was founded in 1917 after two inventors failed to sell their four-wheel-drive components to major automakers like Ford. The company branched out into specialty trucks like snowplows, and that's what landed it its first major U.S. military contract during WWII: building snowplows to quickly clear airstrips and military bases.

Today, the company is still a major defense contractor and specialty truck maker, manufacturing garbage trucks, fire trucks, construction vehicles, and light armored military vehicles, among many others. Business is booming, and the stock is, too: A $7,000 investment in Oshkosh just nine years ago would be worth more than $77,000 today.

And the company looks like it may continue its rapid growth. Oshkosh derived 26.6% of its revenue from its defense division in its 2017 fiscal year, which ended Sept. 30. Increased federal defense spending may push that percentage even higher next year.

Also, with talk of a big infrastructure package coming in 2018, Oshkosh's access equipment segment, which serves the construction industry, may see a similar boost. The segment accounted for almost half of Oshkosh's 2017 sales, and reported a 38.1% increase in net earnings in the most recent quarter. Oshkosh is looking like it's going to continue its growth.

Disrupting an industry

Low-cost air carrier Southwest Airlines hasn't been around as long as Oshkosh -- it didn't begin flying until 1971, and didn't fly outside of Texas until 1978. But its growth trajectory has been every bit as extraordinary as Oshkosh's. In 2003 -- just 32 years after its first Texas flight -- it became the country's largest air carrier based on number of domestic originating passengers, a distinction it holds to this day. It's also the second-largest U.S. carrier by market capitalization, just barely below Delta Air Lines.

Given such rapid growth, it's easy to see why a $7,000 investment in Southwest just nine years ago would be worth more than $55,000 today.

But Southwest doesn't seem to be slowing down either. It plans to start offering flights from the West Coast to Hawaii this year -- possibly paving the way to break Hawaiian Holdings' monopoly on inter-island flights in the Aloha State. Fears that other discount carriers like Spirit Airlines or JetBlue Airways would seriously eat into Southwest's profits haven't materialized, so Southwest is looking poised for a smooth flight into the new year.

A novel idea

Cintas was founded in Cincinnati in 1929 by Doc Farmer, an out-of-work circus performer. He had an idea that was every bit as disruptive as low-cost airfare: He collected used rags that factories had thrown away, washed them, and sold them back to the factories. That may not sound particularly earth-shattering, but it was cheaper for his customers than constantly buying new rags.

In the 1950s, Doc moved into the related business of uniform rental, and by the late 1960s, the company had begun to expand nationally. It used its existing nationwide distribution network to offer other business services, including floor mat rental, restroom restocking, and fire and safety equipment servicing. These industries are incredibly fragmented, and Cintas has been able to expand by leveraging its size and by gobbling up competitors -- like uniform renter G&K Services, which Cintas absorbed last year.

Although uniform rental still makes up 81.4% of overall company revenue, those other business services like fire and safety equipment servicing are growing more quickly, with 10.7% year-over-year organic growth in the most recent quarter. The overall business -- and its share price -- has grown by leaps and bounds as well. In fact, in just nine years, the company would have turned a $7,000 investment into more than $56,000, thanks to price increases and consistent dividend increases, like the 21.8% increase in 2017.

As the market leader, Cintas should be able to continue offering investors superior returns.

Investor takeaway

The most important thing to take away from the stories of these three companies is that you don't need to get in on the ground floor of a business to make money. All three companies have been around for well over 40 years -- and Oshkosh for more than 100 years -- and yet a $7,000 investment less than 10 years ago would still have produced amazing returns.

These three companies look like they still have room to grow over the next 10, 40, or even 100 years. They're definitely worth a second look.

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John Bromels owns shares of Cintas. The Motley Fool recommends Cintas. The Motley Fool has a disclosure policy.