When Deary, Idaho native Isaac French's dad saw an abandoned train car on a neighbor's farm, he knew there was potential for something great.

The car, built in the 1900s, had been sitting in the same spot for decades. The wood was rotting, algae was growing and there were about 20 cats living inside, French, 27, tells CNBC Make It.

Train car number 306 originally ran on the Washington Idaho & Montana Railway from 1909 until the 1950s.

It took several years, but in 2020 the family purchased the train car for just $3,000.

"[My dad] had the faith and the vision for it and I'm so glad he did," French says. "There's something so rewarding about taking an old structure that was so lovingly built, and breathing life back into it."

It also took quite a bit of time for the family to find someone willing to move the 61-feet-long structure to their 145-acre piece of land.

"It's just a beautiful, secluded place in nature," French says. "We chose the highest point on our property so that we could capture these epic views."

The move cost around $10,000.

The family then spent $137,000 and six months renovating the structure that they intended to use as an Airbnb. Expenses included building a platform, refurbishing the floors, adding a bathroom, landscaping, and furniture.

French, his parents and his siblings did most of the work themselves, restoring the train car to mimic the original design. They hired subcontractor friends for the HVAC and electrical work.

French hand-painted the lettering on the exterior of the car based on an old photo they found. The train car even has its original windows.

"In the summer, we open these up, let the breeze blow through the car. It's just beautiful. In hay season, you smell the rye grass wafting through the car," French says.

To make the train car livable, French and his family converted the passenger room into a sitting area, added a kitchenette, and a gas potbelly stove.

They built a bathroom with a barn door and outfitted the train car's former mailroom into a bedroom with a king-sized bed.

"Our guests absolutely love it. They wake up in the morning and look straight out onto these beautiful panoramic views of the countryside. It's a really epic place to sleep," French says.

To enhance the experience, they added a mirrored sauna, hot tub and firepit right outside.

"The idea is to reflect the nature surroundings. Since we had these beautiful pine trees and this spectacular view, we thought it would be a cool juxtaposition of new and old," French says.

Finding success on Airbnb

Despite being in the middle of nowhere, the train car was an instant hit on Airbnb. The listing became one of the most successful Airbnb locations in the country, according to Fast Company.

It costs between $325 and $350 a night to stay in the Restored 1909 Train Carriage.

"What I love about it the most is that there is a sense of history and a story that's already built in," French says.

In the first year, the train car had 90% occupancy and $14,179 in revenue. Since then, revenue has increased to between $75,000 and $90,000 a year, according to documents reviewed by CNBC Make It. This year, French says it's projected to bring in $105,000.

In 2023, the train car was booked for 231 nights on Airbnb. It has about a 65% profit margin, with 30 to 35% of overall revenue going towards cleaning costs, ongoing small maintenance and repairs, property taxes, and insurance.

The family knows they could raise the price per night of the train car's stay, but French says they don't plan on doing that because they find it fulfilling to play hosts to people from all over who want to experience a piece of history.

"How many old buildings and old stories and old train cars are just sitting out there waiting to be discovered and loved," French says. "And I think that's the key. You have to have some love and some inspiration to participate in a project like this and breathe new life into it."

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