However, having lived in an area similar to this previously, I felt confident that I could avoid most of the pitfalls of investing in a C class neighborhood as long as I stayed somewhat active in its management and check ins.

Some risks I saw come to reality: increasing condo fee, board threatening to pass rental restrictions on units, including on existing landlords/owners.

I have complete confidence he will be paying off earlier and won’t be missing payments, so that is not one of my concerns.

I also include utilities in the rent so adding a second person increases the utility usage and costs me another $30 or more a month.

If its in a good neighborhood it might increase its value on a long term basis. 

Alone with increasing the number of rentals I also have got in better neighborhoods so better rents.

Take that seriously to increase your chance of success.  

And even when I have found answers that I'm somewhat confident in, I don't want to risk money based on whether or not I found the right website on Google or whether I interpreted the relevant Idaho legislation correctly.My understanding of the Idaho law I linked to is that there isn't a redemption period after the sale takes place.I'm quite new to this, so I don't have a title company that I use regularly, but that is definitely a valid point as I'm sure they have insight into the process and be able to help clarify it. 

Use seller financing to hold the note to increase your profits, not sell the note to lower your profits.IRR would be the best way to calculate your ROI.

If this becomes a long term tenant, you just established/allowed 2 things to happen:1 - You just established a lower rate as a starting point, with all rent increases to them coming off this amount.