In 2003, when Marnie Oursler was 24 years old, she bought her first house.

The home, in Bethany Beach, Delaware, where her family had vacationed when she was a child, was a $US240,000 fixer-upper that cost her the $US18,000 she’d saved over the past few years working for a realtor after graduating from college.

“I was making like $US11 an hour,” Oursler says, “doing anything to save money: feeding cats, washing cars. I literally ate peanut butter for two years.”

The house on which she spent her savings, she remembers, was “in a great location, but it was a dump. I didn’t have any money left over after I bought it, and everyone said I was crazy. I did it anyway, and fixed it up. I did most of the work myself because I couldn’t afford anyone else.”

Using skills she’d learned from her father, a builder outside of Washington, DC, Oursler started by ripping up the carpet, holding a painting party with friends, and, she remembers, building a driveway “with my bare hands in the rain, using three-quarter inch bluestone.”

She sold it nine months later, for $US350,000.

Realising that she had an interest in, and an aptitude for, real estate, she took a new job in sales for a homebuilder. She used the money from her first house’s sale to buy a lot in an even better location, closer to the ocean, where she started building another home.

“People would approach me and say, ‘You’re really good at this, would you build me a house?’ and I was like, ‘No, I have a job, I’m just doing this because I need a house,” Oursler remembers. She ended up living in that house for two years, until she sold it in 2006 and bought another lot, even closer to the ocean.

In 2007, Oursler was tracking and charting real estate patterns — a habit she picked up during her first job out of college — and realised the market was turning. She called up a couple who had approached her while she was building her own home and asked if they still needed a builder.

“I kind of had to beg them for a meeting,” she says. “I was a little relentless.”

When the couple agreed to take her on as their builder, Oursler remembers calling her dad to find out how to do an estimate. “He was like, ‘You’re so stupid, this is 2007! Don’t do this,'” Oursler laughs. “So I quit my job and started my company.”

That company is Marnie Homes, a custom building company in Bethany Beach, Delaware, with three full-time employees aside from Oursler. The company builds about seven area homes a year, mostly second homes and homes that are intended to be primary residences once the owners retire. It also takes on miscellaneous projects, such as renovating office spaces.

When she first started the company, Oursler says, it made $US450,000 in revenue that first year. That number has grown steadily. Marnie Homes is on track to earn nearly $US7 million by the end of 2015, and over about $US9 million in 2016.

There’s no such thing as a typical day, Oursler explains. “I’m usually in the office half of the day and on the site half of the day,” she says. “I do a lot of calls and meetings with clients, I still do all the budgets and estimates. I work with my treasurer dedicated to managing the budget for each house, a coordinator in charge of monitoring all the selections, and a project manager who’s in the field 95% of the time. I also do a lot of design work. That’s why I love it — there could be days where I never get into the office, and days where I can’t get out. It’s fun. Every day is different.”

She’s getting ready to build another house for herself, which she says will be a lot different from the house she bought at 24 (“We used to call it ‘the wigwam'”).

In 2013, she got her MBA from the Duke Fuqua School of Business. “It’s really helped me to be seen in a different light,” she says, “as not the traditional builder. People might take me a little more seriously now than when I made $US11 an hour and was feeding cats — but I don’t know that I think of myself as much more serious.”

Oursler advises people who want to start their own businesses to “think outside the box, and not be discouraged by rejection. For anybody, that’s a huge challenge, but it’s really important to have support from your friends and family, and that determination inside to keep fighting every day for what you really want to do.”

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