David Do doesn't have much of a system when it comes to his credit cards.

Sure, he keeps them organized. When he's not using them, his 30 or so active cards live in a binder in plastic sheaths like Pokémon cards. He has the commensurate apps for all of them, too, which helps him keep track of his spending and due dates. But that's about the extent of it.

"For people who do travel hacking, like what I do, they have the proper way of using an Excel sheet. I don't use an Excel sheet at all," says Do, 33. "Truthfully, I just go by memory and just be like, 'Oh, yeah, I did apply for this card last year. So let me just keep a timeline of when the annual fee is due, or when this credit card statement is due.'"

Travel hacking means strategically using credit card rewards programs to score free or discounted flights and hotel stays, often by taking advantage of bonuses for opening new cards or transferring points between programs. It's a hobby that requires vigilance – both to ensure that you snag the best deals when they arise and to make sure you don't accidentally rack up debt across your array of cards.

It's easy to see why some travel hackers are serious about their spreadsheets. It's hard to argue with Do's results, however. Besides a mortgage on a 2-bedroom, 2-bathroom townhouse in Riviera Beach, Florida, he doesn't carry any debt. He dutifully invests a healthy portion of the $78,000 salary he earns working remotely as a social worker for a group of primary physicians' offices.

Since 2017, he's earned and redeemed well over 1 million credit card points and miles, using them to help fund trips to 33 countries.

"I'm hoping to do 35 by the time I'm 35," he says.

'[My parents] always lived below their means'

Do owes a good deal of his financial success to his family, in more ways than one. He learned a lot from his parents, refugees from Vietnam who he says were loving providers and yet careful about how they spent.

"My parents were always very, very frugal with things. They we were strict about eating out, things to buy. If we wanted something, they were always like, 'We can't afford that right now,'" he says. "I think in the grand scheme of things, they were being smart with their money … they always lived below their means."

They kept on top of Do when it came to schoolwork, too, which paid off. Thanks to a mix of scholarships and grants, he was able to graduate from University of Central Florida in 2015 with a degree in psychology and just $10,000 in student debt.

Moving back home, 'I could prioritize' getting out of debt

"Towards the end of my undergrad, my brother had passed away, and I didn't really, you know, have a solid idea of what wanted to do with my [life]," he says. "So as soon as I could graduate, I immediately went home."

Living with his parents in West Palm Beach allowed Do to support them emotionally while giving himself time to figure things out, professionally and financially.

After he started working as a coordinator at a treatment center for adults and children with mental health and substance abuse issues, he realized he was interested in social work. He enrolled at Barry University in Miami in 2017 and graduated two years later with a master's and about $40,000 in additional student loan debt.

Do embarked on an aggressive strategy of repaying his loans and bolstering his savings. "Living at home made it a lot easier, because I could prioritize certain things I needed to," he says. "So I pretty much budgeted maybe over half of my paychecks [toward] all the student loans."

He made his last payment in early 2020. The following year, Do bought his current home, a $182,000 townhouse, with a 3% down payment.

How he spends his money

Here's how Do spent his money in March 2025.

• Housing and utilities: $1,875 on his mortgage, private mortgage insurance, homeowner's association fees, water and electricity
• Dining and groceries: $962
• Savings and investments: $950 invested in his 401(k)
• Discretionary: $874 on entertainment and tax preparation
• Insurance: $294 on health, dental, accident, auto and accident policies
• Travel: $184 on plane and train tickets
• Transportation: $156 on parking, tolls and ridesharing
• Health: $111 on prescriptions, copays and his mom's monthly health insurance premium
• Phone: $71
• Subscriptions and memberships: $17 on Planet Fitness and iCloud

Do's living expenses make up the biggest chunk of his budget, though he's quick to acknowledge that he got a pretty good deal. "Fortunately, I was able to buy at a time where the interest rate was relatively low, so, that kind of helped a bit," he says. "I do have HOA fees. That's a little bit hefty, but it's still a pretty decent value for what it is in South Florida."

Do's mortgage rate is just a tick over 3%. Even with a $503 HOA fee, his monthly housing payment comes to just over $1,700. Utilities run him an additional $156.

His next biggest expense in March was food. The majority of that came from dining out, though Do says he's working on getting handier in the kitchen.

Do uses credit cards to his advantage. Every cent he spent at a restaurant in March, for example, went on a Discover card offering 5% cash back that month on dining purchases. Plane and train tickets went on a travel card from Capital One. Amazon purchases went on a Chase Amazon Prime card.

Each month, Do examines which of his cards offer the most generous rewards and divvies his spending accordingly. "It really just depends on what month it is, because each credit card's points have … you get extra cash back on the category, like, let's say, for example, groceries or gas," he says.

And he signs up for new rewards cards when doing so is likely to benefit him. "I know if I have a big expense coming up, let's say, for example, I have to pay for tuition, or I have to pay for car insurance, or I have a big quarterly tax I need to pay, then I'll try to time it accordingly with one of the credit cards that offers a big sign-up bonus," Do says.

Balancing saving with 'a fulfilling life'

Do is happy to redeem the points he racks up — he estimates he takes seven or eight trips a year — though he looks to get bang for his buck. Like most travel hackers, he looks to maximize his points' value by transferring them between loyalty partners, which can offer bonuses.

While Do currently has about 370,000 points saved, you won't see him flying in first class anytime soon. "It's always been economy for me. I could redeem it for business, but it just, I can't really sacrifice the points," he says. "I'm more of a budget traveler."

His next trip? "Right now, me and my friend, we're hoping to plan a trip to believe it or not, Uzbekistan, Azerbaijan and Georgia," he says. "So that's kind of being in the works right now."

Over the longer term, Do plans on achieve a version of financial independence known as "Coast FIRE." Once he's saved a certain amount, the thinking goes, he can let that money grow until he reaches full retirement age while he scales back the amount he works, perhaps even by going part-time.

Currently, he has about $250,000 saved across workplace and personal retirement accounts, taxable brokerage accounts, health savings accounts and cash accounts. Between savings and investment gains, he hopes to push that number over $1 million, even if it's not what he necessarily needs to "coast."

"My goal right now is to contribute as much as I can to retirement, but also trying to live a fulfilling life," he says. "And with my job being flexible, I think it's giving me that opportunity, too."

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