Since retiring at age 30 in 2020, Purple has been globetrotting with her partner.

"I'm very happy," the now-34-year-old, who goes by Purple online and in the media to maintain her privacy, tells CNBC Make It.

"Some people like having a lot of structure, and sometimes retirement is a challenge for them, but I'm very good at doing nothing and relaxing and finding new random hobbies," she adds.

In 2015, inspired by her like-minded partner, Purple joined the Financial Independence Early Retirement, or FIRE, movement with a goal of retiring in 10 years. But thanks to diligent investing and a commitment to low-cost living, she reached her investment goal of $500,000 in half the time and retired five years ahead of schedule.

Part of her strategy both in saving for retirement and making her savings last was figuring out how much money she realistically needed to live on and sticking to that amount. Prior to retirement, Purple found she could live comfortably on around $20,000 a year. She splits rent with her partner, but otherwise keeps her finances totally separate.

Since retiring in 2020, Purple has managed to travel to 13 countries and 16 U.S. states, learn Spanish, try new hobbies like birdwatching and see friends and family around the world all without ever spending more than $24,000 in a year, according to documents reviewed by CNBC Make It.

So far, her most expensive year in retirement was 2023; she spent a total of $23,290. As of November 2024, she's on track to keep her spending to around $23,400 for the year, despite traveling to Costa Rica, Canada, Iceland, Switzerland and more.

Here are four strategies that help Purple stick to her spending goals in retirement. 

1. Eliminating major expenses

Purple has chosen a nomadic life in retirement, eliminating many of the major expenses other people have. She doesn't own a house or car, or hold a long-term lease on a home. She doesn't have any pets or children either. 

"When people are surprised at how much I spend, I like to list off what are usually the major expenses per household, and I don't have any of them," she says. "Without those major things, it's pretty affordable for just little old me."

Her monthly "rent" is typically a payment to an Airbnb host, but she also spends some time staying with friends and family or housesitting.

In 2023, she spent 271 days in Airbnbs, 70 days with friends and family, and 24 days housesitting, she says. She typically lives in one place for at least a month, often earning her discounts on Airbnb stays, since the website allows hosts to offer discounts for weekly or monthly bookings.

2. Travel hacking with credit cards

To get from place to place, Purple often flies first class. But she doesn't pay the thousands of dollars some plane tickets can cost. 

"If I can find a way to get something expensive for less, I do that," Purple says. 

She discovered travel hacking — signing up for credit cards to take advantage of rewards — in 2015 and has since saved thousands of dollars on flights around the world, she says. She flew first class from Singapore to Sydney, Australia, in September 2023 for a fraction of the ticket's $4,000 full price.

To score these deals, she applies for credit cards that don't charge an annual fee in the first year and offer high sign-up bonuses. She hits the minimum spending requirement, collects the bonus, pays off the card and closes it 11 months later, just before she's charged the annual fee.

3. Balancing expensive locations with cheaper ones

Being retired means Purple can be flexible in booking trips and deciding how long to stay in any given place. That flexibility, along with her travel hacking, allows her to save on flights without scrimping on comfort.

Similarly, Purple tries to strike a balance between high-cost trips and low or no-cost stays. She typically stays for at least a month, regardless of the local cost of living, but when she knows she will be in a pricier area for a spell, she aims to make her following destination a cheaper one.

This year, she followed time in Mexico, a relatively low-cost destination, with a trip to Amsterdam, which is on the pricier side, for example.

4. Spending her money intentionally

Since committing to FIRE and retiring, Purple has become highly intentional with her spending. Early in her advertising career, she often spent money on clothes and accessories until she realized those items weren't improving her life at all. 

She's now able to "spend lavishly on things that really make me happy," in part because she's only spending on what brings her joy, like travel and dining at nice restaurants.

Even when it comes to bills like her phone service, Purple asks herself if a higher price tag is worth it and if not, she finds a cheaper alternative. 

"Figure out what actually makes you happy and spend on it and then save the rest," she says.

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