A finance expert has revealed the one simple question to ask when buying a car - swearing it can make owning a vehicle much cheaper.

TikTok content creator Erika Kullberg, who often posts financial and legal tips to her account under Money Lawyer Erika, acted out a scenario between a car dealer and a prospective buyer.

In the scene, she pretends to be a person shopping for a new car, telling the salesman she likes the Tesla and that her monthly budget is $500.

In response, the salesman says it is a 'stretch' because it is on the lower end, but he will see what he can do. 

After talking with the manager, he comes back with the 'good' news that he managed to get a $400 a month payment. 

TikTok content creator Erika Kullberg, who often posts financial and legal tips to her account under Money Lawyer Erika, acted out a scenario between a car dealer and a prospective buyer

TikTok content creator Erika Kullberg, who often posts financial and legal tips to her account under Money Lawyer Erika, acted out a scenario between a car dealer and a prospective buyer 

While it sounds better, as it is less to pay per month, Erika pointed out that means you will actually be making the repayments for longer.

'It's a trick to make it seem cheaper,' she explained.  

Instead, she advises people to ask what the total cost of ownership of the car is instead.

The clip has since garnered over 2.4 million views, with people sharing their thoughts on Erika's advice - some arguing it is common knowledge.

'Is this not just common knowledge? We need to change what we teach in school,' one user declared. 

'Never tell them what your monthly budget it. Negotiate the price, not the payment,' added another.

'I used to sell cars. Never bargain off of a payment amount, always bargain off of the cost of the car, period,' another user advised. 

Between 80 and 85 per cent of new vehicles purchased by Americans over the past three years are financed, and as many as 40 per cent of used vehicles, according to a recent report from Experian. 

In the scene, she pretends to be a person shopping for a new car, telling the salesman she likes the Tesla and that her monthly budget is $500 (stock image)

In the scene, she pretends to be a person shopping for a new car, telling the salesman she likes the Tesla and that her monthly budget is $500 (stock image)

The clip has since garnered over 2.4 million views, with people sharing their thoughts on Erika's advice - some arguing it is common knowledge

The clip has since garnered over 2.4 million views, with people sharing their thoughts on Erika's advice - some arguing it is common knowledge 

Jase Patrick, who was a car dealer for fifteen years, recently shed light on the often deceptive tactics salespeople use that can land customers with a larger bill. 

The former car salesman that he helps to make people aware of the methods used to increase monthly payments before signing the papers.

'The price online is only to get people into the dealership, it has zero correlation with what they pay,' Patrick warned.

One trick that Patrick warns car buyers to keep a wary eye on is if they feel rushed to sign documents by a salesperson.

Patrick told American Prospect about a first-time buyer, Mario from Corona, California, who was being rushed and was told by a salesperson that he was not able to see his auto loan agreement in full.

'This is the ideal customer,' Jase told the publication, 'this is what [salespeople] train for.'

By rushing Mario through an unfair finance agreement, the 20-year-old nearly signed a deal that would have cost him more than $20,000 than it needed to over the life of the loan, according to Patrick.