Owner finance can be a great strategy, but it must be done properly. I agree with Brian in that you will be fine with an RMLO, and that is a good way to go anyway to ensure that you create good marketable paper which can be sold to a note buyer. Also I recommend parking it with a licensed servicer to ensure compliance in servicing as well. Allied and FCI are the ones I use, but there are others. Servicing costs are not much, maybe $20 per month. The Dodd-Frank and SAFE rules are there to protect consumers. You are not as restricted when doing a commercial loan, i.e., loan to a business entity.
Regarding the discount when selling the note, it depends on the credit worthiness of the borrower, the quality of the underlying asset, LTV, loan terms, and the payment history. A brand new note with no history will sell at a steeper discount because the buyer is taking more risk than with a seasoned note. The more information you collect as part of creating the paper, the easier it will be to sell. If you have it professionally serviced, that makes it easier to sell to because the payment history is documented.
Most performing note buyers I know are looking for a yield in the 12-14% range, but again this is dependent on the factors I mentioned. I ran the math on your 109K note @ 9% over 5 years and found that selling it at 92K would provide a 14.38% annual yield to the buyer. So, seems like a reasonable deal for the buyer, especially if he knows the borrower personally.