Is a promissory note the right instrument for a unit owner to sign who owes money to the HOA for repairs to her unit?

My HOA paid for repairs to leaking pipes of a unit owner because the unit owner (who doesn't live in the unit) wasn't responding to requests to repair the leak and the leak was causing damage to the unit below. The unit owner agreed to repay the costs incurred to fix the leak, but doesn't have all the money right now and requested a promissory note to repay the amount over 7 months. Is a promissory note the right legal document in this case or is some other document better?