A couple who engineers all their trips to cost 'nothing' explains how they broke even on a $37,000 tour of the US National Parks

Courtesy of Lauren and Steven Keys

Lauren and Steven Keys.

• Lauren and Steven Keys, a millennial couple from Florida, traveled to all 61 US National Parks in 2019.
• While the trip cost about $36,800, they earned roughly the same amount during that time through side hustles, part-time work, and passive rental income.
• They paid for the trip upfront with savings, but their nest egg didn't lose value in the end.
• Read more personal finance coverage.

Steven and Lauren Keys are obsessed with traveling. They're also obsessed with financial prudence. At just 29 and 30 years old, they've crafted a life that fosters both.

Throughout spring and summer 2019, the husband-and-wife pair, who are based in Florida and run a blog called Trip Of A Lifestyle, traveled throughout America on a quest to visit all 61 National Parks.

In just seven months, they traversed the continental US in a renovated van and flew to Alaska, Hawaii, American Samoa, and the US Virgin Islands.

The total cost of purchasing the van, food, accommodations, transportation, gas, airfare, insurance, and incidentals came out to $36,875 - just shy of the amount they earned during that same period, the couple told Business Insider.

They used part-time work, side hustles, and rental income to break even

Amid the long-distance driving and on-the-ground exploration, Steven worked part-time for his employer at a reduced rate, clocking in around 10 to 12 hours a week of work. Lauren picked up a freelancing job doing marketing and social media management a few hours a week.

Together, they pulled in extra cash as photographers for hire and utilized rewards credit cards to earn cash back on their purchases. And perhaps most significantly, they rented out their mortgage-free condo in Gainesville, Florida, for their entire seven-month absence.

In total, they brought in about $37,000 in income (before accounting for self-employment taxes) during their travels.

Courtesy of Steven and Lauren Keys

The couple traveled between parks in their renovated van.

"In order to get to a financial position where we had the freedom and confidence to try something like this trip in the first place, we have lived pretty modestly for a long time," Steven, a former high school teacher, told Business Insider via email. "For the last seven years or so, our total household expenses have typically ranged somewhere between $18,000 and $27,000 per year, for the two of us combined."

Since graduating from college in 2012, Lauren and Steven have consistently saved 50% of their modest incomes. They keep most of their savings invested in fairly liquid stocks and bonds and their balance was in the six-figures prior to their National Parks trip, they said.

"It's certainly not necessary to have anywhere near this much before trying what we did, but having a buffer of investments definitely allowed us to dive into something new without fear," Steven said.

Their ultimate goal is a 'work-optional' lifestyle

But it's not the first time the Keys have traveled virtually for free. In 2015, they pared down their belongings and took a six-month honeymoon in Hawaii. Thanks to income from side hustles and contract work - and some penny-pinching habits - they broke even.

Steven and Lauren said their frugality is driven by their ultimate goal: financial independence. But the system they've engineered allows them to enjoy their money now without making massive sacrifices.

"The idea is to reach a point where the returns on our passive investments exceed our living expenses, so work becomes completely optional for the rest of our lives," Steven said. "Some people would call it 'early retirement,' but we prefer to think of it as 'work-optional.'"

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