Doubling the size of her loan is not what Christina Resuello expected when she signed up for a $5,000 line of credit with Marlin Financial. But that's what happened, she said, because of a misleading debt cancellation product the company included in her agreement."I was like, 'I'm not paying this. I want to redo this,'" she said. "I don't want to pay back that kind of money."The Boca Raton resident is among a smattering of consumers statewide who claim they were duped by Miami-based Marlin.Resuello, like others, went to Marlin for a loan against her car. Marlin's website says it offers title loans for cars and boats — although Florida Office of Financial Regulation records show it is not licensed to issue title loans. Instead, its product is actually a longer-term loan that uses the borrower's car as collateral.According to Allison Friedman, a lawyer representing Marlin, the debt cancellation product at the crux of most disputes is an optional add-on that wipes out any unpaid debt left on the loan should the car be totaled. And it is pro-rated. Borrowers say the confusing product, which they could not opt out of, wound up doubling the principal balance to pay off.The Better Business Bureau has received 17 complaints about the company within the past three years. Often, the BBB said on Marlin's page, the complaints follow a particular pattern:"Consumers allege they took out a loan with Marlin Financial, and when they went to pay off their loan a few months later their loan had significantly increased," the site said, sometimes doubling the loan balance. Issues with Marlin in Tampa Bay surfaced in June when two Tampa residents alleged that Marlin marketed the debt cancellation as insurance. The $24,500 total of two loans they took out through Marlin, the complaint said, came with an unexpected additional $36,000 in debt cancellation product.Previous coverage: Two Tampa residents sue Miami auto lending firm, alleging deceptive practicesThey're not the only ones suing Marlin.Friedman, Marlin's lawyer, would not say how many court cases she was involved in with her client. But a search of the 10 most populated counties in the state, as well as Pasco County, show eight lawsuits involving Marlin. Three are local and involve disputes about the debt cancellation product. They are the only instances when Marlin is the defendant.In one case, Temple Terrace resident Isaiah Burgman borrowed $10,000 from Marlin against his 2015 Jaguar. Despite repeatedly saying he did not want the debt cancellation product, the complaint says, he accepted the supposedly optional product after "urging" by Marlin."Marlin in practice absolutely requires every loan customer to accept debt cancellation as a condition to obtaining a loan," the complaint, filed July 31, said.Friedman insists customers are not forced to pay for deb cancellation. The only time Marlin requires it, she said, is if a borrower cannot show that they are insured for the year."If you cannot provide proof of insurance for the year, then they would like for you to do the debt cancellation," she said. If the customer doesn't like that, "You don't have to accept a loan from them."Times senior researcher John Martin contributed to this report. Contact Malena Carollo at [email protected] or (727) 892-2249. Follow @malenacarollo on Twitter.