How a $91 million loan on the Marlins ballpark will cost Miami-Dade $1.2 billion

The good thing is, at least they got that home run display to show for it.

Miami-Dade will use hotel-tax revenue to pay off the bonds. But payments don’t kick in until 2026. Once they do, they get very costly very quickly. The first payment, for example, totals $260,000. The fifth jumps to almost $8 million and the 10th tops $20 million. Payment No. 18 brings the big hit: $118 million comes due in 2042 alone.

The high interest comes from the penalty Miami-Dade must pay in exchange for a repayment plan that lets the county delay by 15 years making it first debt-service payment to the Wall Street lenders who bought the bonds.

“It’s an expensive way to borrow money,’’ said Frank Hinton, head of the county’s bond program. “You’ve got $1.2 billion to pay back. It is a lot of money.”

Because Miami-Dade couldn’t afford a straight-line paydown of the loan — like a home mortgage — the finance team had to be more creative in borrowing the money on Wall Street. Unlike most bonds, these can’t be repaid back early either.