When you deal with a seller's note, what are the odds that the buyer will pay the seller's note in full? How do you evaluate the risk of that into the total valuation for the company? Assume there's no earn-out portion. (I know some recourse exists where the buyer would have to hand the business back to the seller, but presumably, if the buyer is unable to make seller's notes payments, the health of the business isn't doing great.)

Also curious for those who have seen a seller's note go unpaid, what were the most common drivers of that?