Blaine Vossler and Mackenzie Edgerton had never even set foot inside a trailer when they quit their day jobs and started a business out of a 1979 Airstream. It also doubles as the husband and wife-to-be's full-time home on the road.

"It was just a random idea," said Edgerton. "We hadn't really seen anyone doing mobile retail, but we were inspired by food trucks."

Vossler and Edgerton, both 29, were high school sweethearts back in Syracuse, N.Y. They moved to San Francisco after college, with student loan debt and in the midst of the recession. She worked in visual merchandising and he worked at a nonprofit -- but they were both uninspired by their day jobs.

So in 2014, they turned a part-time hobby into a full-time business, The Local Branch Co., selling hand-printed apparel, leather bags, jewelry and home goods.

They were entering the increasingly popular, millennial-dominated "maker" movement -- where budding entrepreneurs peddled "Made in America" goods.

But mobile retail was virtually uncharted territory.

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The desire to build up a community and provide resources for fellow mobile small business owners prompted 37-year-old Stacey Jischke-Steffe to co-found The American Mobile Retail Association (AMRA) in 2013.

"There's a misconception that because we're mobile, we're not serious and we don't have business licenses," said Jischke-Steffe, whose own roving boutique is aptly titled Le Fashion Truck. "We're not traditional brick and mortars, but that doesn't make us any less legitimate."

(For the record, Jischke-Steffe doesn't live in le truck).

AMRA currently has 102 members, and consults for 20 to 25 aspiring mobile business owners each month. But Jischke-Steffe estimates there are at least four times that number nationwide. A major part of the appeal? Significantly lower startup and overhead costs than brick and mortar operations, while maintaining the face-to-face customer interaction missing from e-commerce.

A 2013 AMRA survey found that on average, mobile retailers spend just under $16,000 on purchasing and renovating a vehicle, and $942 a month on gas, insurance, and vendor fees at event spaces. In the United States, 56% of new business owners use debt financing to fund their startups, taking out an average of $53,000 in loans during their first year, according to a 2008 survey from the Kauffman Foundation.

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After checking out the Bay Area for both studio and retail spaces and finding that they'd cost at lest $1,000 per month, Vossler and Edgerton came to a hard realization. "There was just no way," said Vossler. "It would be so expensive."

Enter the 1979, flat-tired, mold-covered Airstream trailer they got off Craigslist for $3,000. A $7,000 renovation, mostly done by Vossler and Edgerton themselves, included a lot of strategic planning to maximize the space. The bed -- the same one they had in their San Francisco apartment -- can flip on its side to store inventory. Open up the sewing bench, and you'll find a stockpile of leather straps for bags and cape buckles. A row of school lockers was turned on its side to hold shipping supplies.

In February 2014, they set off across the country for a planned one year on the road.

Traveling to craft fairs and music festivals that see crowds between 10,000 and 80,000 people, The Local Branch was profitable in its first year.

"Even in a city, I don't think that stores normally get that type of traffic," said Edgerton.

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It's one of the advantages Jischke-Steffe has also identified with her Los Angeles-based fashion truck. "You can move with the trends, and be in areas you'd never be able to afford as a brick and mortar shop," she said.

But it comes with its unique challenges, too. "You definitely have to be comfortable with unpredictability," said Vossler.

"It's really dynamic, and there's a lot of problem solving and a lot of things that take someone to be flexible to be able to do this full-time," added Edgerton.

Still, the couple has opted to extend their nomadic adventures at least through the end of 2015. Hopping from campground to campground, they spend about $10 - $20 per night to park their 200-square-foot tin can. That includes hookups to electricity, running water and sometimes WiFi. The shower facilities come in handy, too -- Vossler and Edgerton decided to rip out the old shower to make room for a modest closet.

"You can live a bit more frugally," said Vossler. "You can experience not only the culture of one city but the culture of so many cities and rural places and really have the best of both worlds."