The 38 year old financial coach spends just 124 a month on

The 38-year-old financial coach spends just $124 a month on groceries – her No. 1 “secret tip” when shopping for groceries

DeFelice takes $120 a week in cash to cover expenses like gas, groceries and drinks with friends.

Corentin Soibinet for CNBC Make It

Carly DeFelice, who runs the Best Money Class Ever online personal finance course, has some key numbers to rely on when it comes to establishing herself as a skilled saver and budgeter. Between her college graduation in 2008 and her 26th birthday, she paid off $35,000 in debt and put away more than $100,000 in investments.

DeFelice, now 38, is a community manager at a coworking space in Austin, Texas, and has grown that number to about $400,000 in cash and investments without ever making much more in a year than her current salary of $58,000. Dollar.

But while DeFelice continues to practice the budgeting methods that have gotten her out of debt and allowed her to build wealth, the smaller numbers might be even more impressive.

For example, consider that DeFelice only spent $123.65 on groceries in September. Given the current inflation situation, it is not difficult to achieve this value in a single trip.

“I guess I spend a few thousand less than the average person because I consciously write down my meals and plan what I’m going to eat for the week,” DeFelice tells CNBC Make It. “My secret tip is to always have a grocery list .”

DeFelice’s grocery income comes from her $120 weekly budget, which she carries in cash.

“I consider this a business expense. So I buy the essentials first – groceries, gas, my car – and then what’s left are good times and time with friends, maybe a new shirt or small gifts.”

That means if she wants to have fun, sticking to her shopping budget is essential. She starts by planning all of the meals for the week, which generally includes large batches of dinners that she can prepare in advance.

The week Make It interviewed DeFelice, the menu included cereal for breakfast; a turkey sandwich, fries and an apple for lunch; and a bowl of salmon, avocado and rice for dinner.

The ingredients DeFelice needed to put together the week’s meals were all written down in the same journal she uses to manage her budget and on a list she took with her to the grocery store.

“I kind of think of Santa Claus — I make a list and check it twice,” DeFelice says.

Once she’s confident her list includes everything she needs to eat for the week, she’ll have the confidence to stick to it and avoid purchases that could drive up her grocery budget.

“The key is that I only buy items that are on the list. This helps me avoid impulse purchases.”

DeFelice applies the same budgeting tactics to dinner or drinks with friends — a $50 line item in her September budget.

“I am very proactive. I make a lot of plans and say, ‘Let’s go to this happy hour,'” she says. While she’s there, she doesn’t have to spend much to have fun with a friend. “I can have a heart-to-heart conversation and build a relationship with a friend and spend about $4.”

Whether it’s grocery shopping or a night out, when you’re intentional about what you spend money on, DeFelice says you’re less likely to spend money on things that ultimately have no meaning to you.

“I have mastered the art of being incredibly social, having a great social life and also being good at saving my money,” she says. “And I think the way I found balance is by realizing that it’s the experience with my friends that matters.”

DON’T MISS: Want to be smarter and more successful with your money, your work and your life? Sign up for our new newsletter!

Get Warren Buffett’s free investing guide from CNBC, which distills the billionaire’s best advice for regular investors, dos and don’ts, and three key investing principles into one clear and simple guide.

CHECKOUT: Charlie Munger: These “basic rules” have made me successful in life – “I had all three with Warren Buffett”