A monthly interest rate can be included on the promissory note. Secure loans with a promissory note.Set loan terms with larger payments at the end. A single final balloon payment for the entire outstanding Principal amount and interest accrued will be paid on or before the day of. Deferral or balloon payment. 21. Get a non-bank loan that's paid back in installments with a secured promissory note. Create and download a promissory note for free!