Callie, 36, and Travis, 39, are married entrepreneurs living in Texas with two children. 

Callie is a self-employed photographer and Travis runs his own property management company, so their income fluctuates month-to-month. They earned a combined $132,480 last year, but have no investments and their fixed costs eat up nearly all of their monthly income, they recently told money expert and self-made millionaire Ramit Sethi on his "I Will Teach You to be Rich" podcast. Their last names were not used.

The couple dreams of taking their boat around the world, being able to enjoy a comfortable retirement and helping their parents financially, but they are pretty lost on how to get there.

"Whatever money we are making, whether it's $2,500 a month or $10,000 a month, I want it to be so intentional that our lives are better because of it," Callie said on the podcast.

Sethi was glad to hear Callie and Travis have an intentional attitude about money, but their spending habits revealed they haven't been as strategic as they need to be to feel truly empowered and meet their financial goals.

Can you afford it? Most people 'genuinely have no idea'

The couple's recent major purchases include an awning and rack for their van and a vacation to Barbados. In both instances, they considered whether or not they could afford the purchase on a monthly basis, Sethi said. They weren't thinking about the big picture.

"[Travis] saw some extra money in his account, he basically said, 'Oh, OK I want that awning. I can afford it,'" Sethi said. "This is very common, and most people genuinely have no idea how to decide if they can afford something."

Like many people, Callie and Travis think about their budget on a monthly basis, rather than an annual one. In doing so, they wound up with purchases — like the trip and the awning — that may have seemed affordable in a month when they had a little extra income. However, it might not have been the best use of that money long-term.

"They literally see something they want, they decide to buy it and then they make up a bunch of reasons later," Sethi said.

Had they compared their annual income with the total cost of these large purchases, they may have realized they'd be struggling to keep up with the payments during months where they weren't bringing in as much money or had other expenses come up.

'Know your numbers'

Callie and Travis work hard and spend their money on things they truly enjoy. That's what a rich life is truly all about, Sethi said. But there's a catch.

"In order to design your rich life, you have to know your numbers," he said. And for people like Callie and Travis who want to pursue entrepreneurship, that's even more important.

Though their income fluctuates the couple could do a better job of anticipating those changes and keeping their cost of living below what they might earn during the slower months, Sethi said. "Otherwise, you might find yourself making minimum wage, working tons of hours, hustling, but never getting ahead."

'Don't lie to yourself'

When it comes to making better spending plans, Sethi analyzed the couple's recent vacation to Barbados. Their lodging was paid for, but the airfares, rental car and dining out led them to max out a credit card with a $5,000 limit "pretty easily," Callie said.

They didn't want to repeat the same mistake on their upcoming trip to Alaska. Sethi's solution: Understand their expected costs and make a plan to pay for them without taking on more debt.

"Until now, they would go on trips, charge up a bunch of stuff, and then get surprised at how much it all cost," Sethi said. 

Sethi asked the couple how much flights, lodging and extras were expected to cost, then pushed them to think a little bigger. When Callie suggested the hotel would cost a "minimum of $600," Sethi stopped her.

"I never do minimum anything on a trip," he said. "Don't lie to yourself before you ever set foot on a plane. What happens when the hotel has a 38% tax and then the only place to eat because you're in Alaska, is at the hotel, which is going to be expensive?"

People consistently underestimate how much they're going to spend on vacations, Sethi said on a previous podcast episode. But by taking the extra time to think through the places you'll drop cash along the way, you can better enjoy your travels without resorting to taking on credit card debt.

Skip the surprises

You know you're going to dine in restaurants on vacation, so make sure you factor tipping into your budget. If you're planning to eat at an airport or get snacks for your hotel room, add a buffer for those things too, Sethi said.

"I would rather you add more money to the budget and come back with a little bit of extra that you didn't spend rather than get surprised with an extra $1,800 you didn't plan for."

Once you have a total cost, you can calculate how much you need to put aside each month to save up for your trip.

Callie and Travis estimated their Alaska trip would cost $5,375 and they have about four months until takeoff. Travis has an upcoming job that will pay him $2,500, which he says will all go toward the trip, so from there they need to set aside another $720 a month.

"We planned out how much it's going to cost. We even left a little buffer," Sethi said. "What I want to see is we are systematically saving every single month to get to the total amount we need."

Check out the full episode here.

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