A 38-year-old woman who grew up playing Monopoly in Nicaragua now has a Yale Ph.D., 4 rental properties, and $268,000 in household income.

The Millennial Money series by CNBC Make It showcases how individuals worldwide manage their finances, including their income, expenditures, and savings.

Cristina Tello-Trillo, despite being the daughter of two economists, was not initially drawn to the field.

"She played Monopoly every single day for at least a year in Nicaragua, which sparked her interest in economics."

Studying economics piqued her interest because she found it fascinating how investing in properties could generate income, requiring her to save money in order to wait for the best property to invest in.

As she studied economics at Pontificia Universidad Catolica of Peru, that initial spark of interest blossomed into a full-blown passion. It was there that she met her future husband, Sebastian, who was also studying the same subject.

Tello-Trillo is a senior economist at the U.S. Census Bureau and her husband is an economist for an international financial institution. They reside in Bethesda, Maryland, with their 5-year-old son, Leo. In 2023, their combined income from their salaries, Tello-Trillo's adjunct professor stipend at the University of Maryland, and their rental property's profit in Washington, D.C. totaled $268,000.

In 2023, Tello-Trillo made approximately $161,600, but anticipates increasing her earnings to $201,564 this year due to the acquisition of three new investment properties in Rochester, New York.

Tello-Trillo's parents taught her about money from a young age, though they didn't push her into economics. They were always frugal and cut off financial support when she turned 19. Despite this, she still carries many of those lessons with her and is happy to spend her earnings on things that matter to her.

She says, "Money is something you work hard for, and if you want to spend it, it's because you truly value something."

Economics 'teaches you how the world works'

Tello-Trillo says that while many people believe that economics is primarily about math, it is actually a social science that provides insights into how the world operates. One of the key lessons she learned is that obtaining a good education can lead to greater financial rewards and, consequently, more opportunities in life.

Tello-Trillo, after completing her bachelor's degree in Peru, pursued her Ph.D. in economics at Yale University. She was admitted as a Ph.D. candidate and also earned a master's degree during her studies.

"I knew that my undergraduate degree in Peru wouldn't take me far in the economics field, so I decided to pursue a Ph.D. to become a researcher and be at the forefront of knowledge in economics."

Before completing her Ph.D. in May 2015, Tello-Trillo secured a job as an economist at the Census Bureau. Her research focuses on inequality, including why women earn less and why people of certain races have worse financial outcomes. She aims to not only explain the existence of these inequalities but also to inform policies aimed at improving them. In 2021, she was promoted to senior economist.

"She believes this job is ideal for her at the moment because she gets to work on topics she enjoys and are relevant, collaborate with exceptional colleagues, and maintain a work-life balance she has always sought."

Earning passive income through real estate

Tello-Trillo, who moved to the U.S. at 23, has been interested in investing in real estate but lacked the funds to begin.

Listening to Bigger Pockets podcasts and observing investors on YouTube further fueled her desire to enter the business world. After completing her Ph.D. and beginning full-time work, she was prepared to make a purchase.

In 2018, she and her husband purchased their first property, an apartment in Washington, D.C. Although she desired to continue acquiring property, the pandemic halted her plans, and she and Sebastian resided in the apartment for four years while amassing funds for a larger house in the suburbs.

In 2022, they purchased their primary residence in Bethesda and started renting out their D.C. apartment.

Tello-Trillo, by 2024, felt ready to become a more serious real estate investor and bought three properties in Rochester in June and July. Though she and Sebastian bought the D.C. property and enjoy the profits together, the rest of her budding portfolio is Tello-Trillo's alone.

"My husband's job is quite demanding, so he doesn't have much time to invest in real estate or search for properties. As a result, we decided that since it's my project, all the property should be in my name, and it will be my money."

Sebastian was initially hesitant about the large financial commitment real estate investing takes, but has since come around after seeing my research and Excel analysis.

In June 2024, she bought two properties with one mortgage for $207,803. The following month, she finalized her third Rochester property purchase for $194,313.

The rental properties were already occupied by tenants when Tello-Trillo closed on them. She earns $2,382 in monthly profit from her four rental units, including the D.C. property, and anticipates making approximately $18,600 in total profit in 2024.

She regrets not starting earlier to reap profits and scale her portfolio faster, but she plans to buy two properties annually until she reaches 20. Currently, she's considering investing in short-term rentals in the Shenandoah Valley, a popular hiking destination in Northern Virginia.

""I'll have enough income to replace my job, which I won't do because I love it, but it's a great supplementary income," she says."

How they spend their money

Tello-Trillo's mother taught her to wait before buying anything, saying, "If it's meant to be, it will come to you." She still follows that philosophy today, she says.

""Now that I have a more stable career, I get things I like, but only if they are truly useful for the family or home," she says."

Her rental properties' mortgage payments are handled by Tello-Trillo, while she and her husband share household expenses equally.

• Housing and utilities: $5,350 for their mortgage, Wi-Fi and utilities
• The total amount saved and invested is $2,312, which includes contributions to a 401(k), Roth thrift savings plan, health care flex savings account, and regular brokerage account.
• Child care: $1,940 for four weeks of camp
• Food: $1,911 on groceries and dining out
• Discretionary: $1,207 on household goods, housekeeper and clothing/supplies for Leo
• Through Tello-Trillo's employer, health and dental insurance costs $653 per month. Auto insurance is paid twice a year.
• Gym membership, Netflix, Spotify, and Amazon Prime subscriptions cost $339.
• Medical expenses: $339 for co-pays and other health-related expenses
• Transportation: $185 on gas and Ubers
• Phone: $141 for their phones and plan

Uber Eats is the family's second-largest expense, with Tello-Trillo confessing that she spends too much on it.

If I don't cook or have time to cook, I treat myself to a delicious ceviche or any Latin American dish.

Tello-Trillo strives to keep her daily expenses minimal and only indulges in items she deeply cares about, such as her home gym equipment. In her leisure time, she enjoys biking, running, hiking, and playing soccer with friends. At home, she has an under-desk treadmill, a stationary bike, and a beautiful road bike that she uses on weekends.

"Exercise-related activities are a no-brainer for me. If I find a useful tool, I'll acquire it."

This fall, Tello-Trillo's son will begin kindergarten, so she had to pay for daytime child care until July, which she is happy about.

Tello-Trillo's expertise in how money affects the world has helped her set herself and her family up for financial success. Although she is knowledgeable about economic indicators such as unemployment and wage statistics, she is not overly concerned about alarming news because "my money is diversified," she explains.

Diversifying the economy is beneficial, as it allows for the potential to profit from other sectors that may not be affected by a downturn in a specific part of the economy.

Tello-Trillo has a total of approximately $412,000 in savings and investments, in addition to her real estate portfolio.

'I will keep working until I cannot work anymore'

Tello-Trillo, despite having a healthy investment portfolio, does not plan on retiring any earlier than necessary.

"I love to work, do research, and manage my investment portfolio. Therefore, I will continue working until I am unable to do so."

She's imparting small financial lessons to her son, Leo, while also demonstrating the importance of working hard to earn money.

She states that she does not want her child to feel too secure and rely solely on a safety net, which may hinder their motivation to succeed in life. She clarifies that she will not be funding her son's college education or leaving him a substantial inheritance.

"That's how life works, so I anticipate him obtaining his own funds and savings."

Her ultimate aspiration is to amass sufficient funds to make a significant contribution through charitable endeavors, with a focus on establishing schools in Latin America, as a tribute to her heritage.

"Education is crucial for achieving success, happiness, and good health."

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