The high-stakes bet worked. Ahern found a receptive lending climate aided by United Rentals' $4.2-billion acquisition of RSC Holdings Inc. Ahern now plans to reduce the average age of its fleet from 71.1 months in 2012 to 52.9 months by December 2017.

"My dad worked his world around no debt, but I wasn't afraid to borrow money," Ahern says. "We know what the customer wants."

Xtreme Manufacturing

Ahern has always been fascinated by engineering, dabbling and experimenting with machines. Xtreme was launched in 2003 to build a better rough-terrain telescoping forklift, the "Swiss Army knife of machines," Ahern says. Xtreme has a 15-model line of forklifts from 5,900 lb up to 70,000 lb, each with roller-boom technology, beefy tubular steel frames and 360° cabin visibility. Ahern Rentals provided instant market exposure, cultivating customers while allowing Xtreme engineers to gauge user feedback and tweak designs.

"Manufacturers were building machines cheaper to fuel parts and new-model sales. It was costing us money to maintain them. So I felt that I could build a better machine," says Ahern. "Our machines cost 15% to 18% more to make, but they last three to five times longer and achieve 20- to 30-year life spans." Xtreme additionally makes flip-trailer trucks as a result of an unmet delivery need. "We couldn't find what we needed," Ahern says, "so we made our own truck."

In 2008, Xtreme began making customizable steel cubes used for offices, restrooms and concessions. For several decades, Ahern took standard shipping containers and adapted them into different modular configurations, but that created challenges because the containers lacked structural strength.

"Once you cut the doors and windows, containers become a flimsy box," Ahern says. "We built a cube with a moment frame that isn't reliant upon shear walls for structural support. They're strong enough to be moved by crane and stacked one atop another."

Xtreme makes four pre-built cube sizes from 8 ft by 8 ft up to 14 ft by 14 ft, each with 10-ft-high ceilings, making transportation convenient. The company sells 500 cubes a year, recently marketing the product as cabins and residences. CEO Tony Hsieh used 43 cubes for a 56,000-sq-ft shopping and entertainment container park development in downtown Las Vegas. The $20-million, 34-outlet complex opened at Fremont and Seventh streets in November 2013, with construction finishing in six months, or about one-third faster than a traditional project.

Snorkel, meanwhile, is now being retooled with the Xtreme rugged design mentality, resulting in 40 electric- and diesel-powered aerial-lift machines with working heights of 12 ft to 126 ft. The company has 200 worldwide distributors, helping take Xtreme global. "I never set any goals. That is a flat process that enables you to rest and become content," says Ahern. "We just keep growing, and I have no idea how big it can become or where it will stop."

Editor's Note: This article was updated on 11/04/2014. A previous version of this story referred to the XTreme XR6538 telehandler with 65,000 lb of lift capacity. The machine was upgraded to 70,000 lb and is now called the XR7038.