Balloon Mortgage to Finance Rental?

[Allen Smith]

I have been looking for the easiest way to finance my first rental property and I wanted to see if anyone has experience with Balloon Mortgages. I have a bank that will give me a ARV loan up to 85%, the 1st twelve months are interest only, and down payment is rolled into the ARV loan. After 12 months it swaps to a 5 year loan 20 year amortized. Bank says I can refinance at any time. Anyone used this strategy? I just feel like their is a big catch with this.