At just 22 years old, Marco and Javier have plenty of time to figure out their financial lives — and they're already making great strides.

"This couple is young, and they are disciplined in a way that I have not seen before," self-made millionaire and money expert Ramit Sethi said about the pair on a recent episode of his "Money for Couples" podcast. Their last names were not used.

With a combined pre-tax income of around $157,000 a year and over $68,000 invested for retirment, they've set up a solid financial foundation for themselves, even while living in New York. But that doesn't mean they're perfect: They sat down with Sethi because they keep having disagreements over how they should spend their money.

"We have a lot of the same shared goals, and I think it's just a matter of how we're executing them," Marco said on the podcast. "I want to make sure we're doing the right things, but I also want to make sure we're doing what we want to do now and enjoy where we're at in life while also doing the right things for the future."

Here's their primary issue when it comes to money, and the advice Sethi offered them.

Fear of 'lifestyle inflation'

Despite living in one of the country's most expensive cities, Marco and Javier have kept their fixed costs — including rent, groceries and other essentials — low at $2,542 per month, or 34% of their income. Sethi generally recommends keeping that category at around 50% to 60% of gross income, so the couple is doing well by that standard.

But they want to move to a new apartment, and since they currently share rent with a roommate, it's likely their costs will increase if they do so. That was one of their points of contention, as they struggled to see eye-to-eye on their budget at times.

"It's funny, because [Javier] makes more than me, [a] significant amount more than me, but I often feel like I am more willing to do more with my income, if that makes sense, than he is," Marco said.

Javier noted that he's worried about lifestyle inflation. A bonus could bring his annual income — already around $110,000 — up to about $155,000 this year, but he fears that upgrading their home or other parts of their lives will get out of control quickly, he said.

"We're not necessarily tracking certain things like that closely," said Javier, referring to the couple's discretionary spending.

'I didn't trip and fall and accidentally swipe my credit card'

Sethi acknowledged Javier and Marco's differing views on money, and commended their transparent communication around the subject. They have full control over their money decisions, and they should feel confident in their ability to reasonably spend on things they truly want, he told them.

Their budget could support an uptick in spending, Sethi said — and the way they already talk and think about money could help them prevent accidental overspending.

"I don't believe in lifestyle inflation," Sethi said. "When I spend money on expensive stuff or stuff that's meaningful to me, I didn't trip and fall and accidentally swipe my credit card. I know what I'm doing — eyes wide open."

Strictly limiting yourself financially, especially when you have more to spend, can become emotionally problematic, he added. Often for people with that money-hoarding mindset, there isn't an amount in their savings or investment account that will make them feel like they can take it easy, the bar keeps going up. And they may miss out on doing things that make life fun like going out to eat or traveling as a result.

"The very habits that make them good with money can also box them in," said Sethi. "That's why optimizers, taken to the logical extreme, become unbearably cheap."

'Life is not just about keeping your expenses low'

Javier and Marco's time paying such a small amount in rent was what Sethi calls a "golden" money moment: when you have a significant surplus of cash after your fixed costs.

These moments are somewhat rare and usually temporary, so it's important to be aware of them and take advantage of them — like the couple has — by beefing up your savings and investing when you're in them, said Sethi. 

At the same time, "life is not just about keeping your expenses low," Sethi told the couple. Their golden moment may be ending as they move into a more expensive apartment, but they should acknowledge that they can afford to pay the additional cost. Moreover, he added, they should know that spending more — particularly to boost your quality of life — can be worthwhile.

"We need to know that money involves numbers, and yes, we should have a healthy savings and investing rate, but it's not here to simply be accumulated or hoarded," Sethi said. "Money is here to provide us a rich life."

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