Stacy Roberts likes to tell her 321,000 followers that her family is rich – in credit card points, that is. Last year alone, she, her husband and their three kids traveled to Spain, Denmark, Austria, Italy, California, Utah and Hawaii all for around $4,300, she says.How does she do it? Roberts says she opens a new credit card each month, allowing her to accumulate around 1m points a year.Though the thought of opening 12 credit cards a year would make most people shudder, Roberts insists it can be done safely: “Every card goes on autopay,” she says, adding that her advice is not for everyone. “Half of the US is in credit card debt, and half is not. [My advice] is for the half that are not.”Roberts is part of a growing cohort of travel points influencers who say anyone can travel the world – sometimes even flying first class – for less than the cost of a nice dinner out. So what’s the catch?The Guardian spoke with Roberts about her credit score, why she never signs up for store credit cards – and what she hopes her children will learn from traveling the world.A typical credit card point is usually worth between half a cent and two cents. But you say you have found ways to maximize your points, taking $83,000 worth of vacations one year for just more than $4,000 out of pocket. How did you pull that off?It’s a question of dedicating the time to doing it. When I got into this, I didn’t have the money to take these trips but I had some time. We open a new card almost monthly. In the last four years, [my husband and I] have earned a [combined] million points at least every year from opening around 12 credit cards a year.At least $30,000 of that [$83,000] value was in two round-trip, business-class flights to Japan with my daughter. We traveled off-season, I took her out of school and we booked last minute. A lot of that value comes from using points at hotels that cost up to $3,000 a night.Typically we travel only on school holidays, but I don’t mind if [my kids] miss one or two days of school so that I can catch a cheaper flight.How much do you have to spend to amass that many points?If the average card requires you to spend $4,000 over three months, and we’re doing 12 cards a year, [that would be] $48,000. We don’t actually spend $4,000 a month; we probably average between $2,500 to $3,000. However, the last few years, we’ve had fun surprises: $20,000 worth of ice damage [to our home] that our insurance reimbursed us for. I put it on my credit card, and they gave me a check. Another year we had to replace our car’s transmission – twice.Last year, we decided to pay our taxes – we owed about $20,000 – on a credit card. You’re paying a fee of nearly 3%, but I calculated it was worth it for the number of miles I was able to get for doing it.Some research suggests people spend more money when using plastic compared with cash, and critics argue that trying to earn a reward can result in consumers justifying unnecessary purchases.Maybe.I personally have always understood if I don’t have the money, I don’t spend it. Usually, if I want something, I either put it on a list of things to buy one day when I have more money, or I tell myself, If you’re still really thinking about that thing in two weeks, maybe we can justify it.I would not say that we spend more, we are just spending smarter. I have to get a root canal next week, and my daughter just got some dental work. It’s very expensive, and I’m putting them on brand-new cards to get signup bonuses, so those are things that we have to spend on, and I’m going to earn a vacation from them.How many credit cards do you have?16.Doesn’t that make you nervous? Americans have about $1.3tn in credit card debt, according to federal statistics. Whenever I hear someone say they opened a bunch of credit cards, it’s usually the beginning of a story about how they amassed mountains of debt.Half of the US is in credit card debt, and half is not. [My advice] is for the half that are not.I have never carried a balance on a credit card in 25 years of having credit cards. All of my cards are on autopay. I’m only using one card at a time. I maybe carry three on me because there are different rewards for different expenses, such as dining out.What’s your credit score?832. When I started doing this, it was in the high 700s. I always pay on time. [Editor’s note: according to FICO, the most widely used personal credit score firm, anything above 800 is considered “exceptional”.]However, you don’t want to apply for credit cards for six months before applying for a mortgage, because if the bank sees a bunch of credit card requests they’re going to wonder.How did you get into using points to travel?I’m the youngest of 12, and [my parents] were pretty frugal people. We’d always stay in hostels and use credit card points for flights. When I turned 18, my dad opened my first credit card. [My parents] taught me to pay them off, so I’ve never had credit card debt.I got married when I was almost 30; we had kids and then we weren’t traveling that much.I wanted to go to Europe, I wanted to go to Peru. I wanted to go around the world. I realized credit cards were the way to do it because it’s not like our salaries – I was a social worker at the time – were increasing to make that a lifestyle.We don’t have fun money or extra travel money. What I can do is give a couple hours a week to learning something new and figuring this out, and then staying organized and on top of it.What’s the catch? What’s in it for credit cards?The banks that issue the credit cards make money every time you swipe your card. Businesses are probably passing the extra cost from credit cards along to [consumers], and raising their prices. Then there are people who don’t pay off their credit cards who have super-high interest rates, so [credit card companies] are also making money on that. For us, we’re paying on time, so we’re benefiting while credit card companies are still benefiting.More from Money whisperers: