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.A balloon payment is a lump sum that's due at the end of the loan term. It is good because it will: Lower your loan repayments. Mortgages with adjustable rates, interest-only payments, negative amortization, or balloon payments are not permitted. The program reserves the right to. Interest-only, negative amortizing, and balloon payments.