Here's the information you'll need to have handy to complete your unsecured promissory note, interest-only with balloon final payment. Here's the information you'll need to have handy to complete your secured promissory note, interest-only with balloon final payment.Interest Only Payments. This means that the borrower will return the money borrowed in a full, single payment. A balloon note is a type of loan where the borrower is required to make regular payments, called interestonly payments, for a specified period. If interest is charged, the rate should be included with a repayment schedule.