@Scott S.
That's great that you picked up your first rental property! Fortunately, with RE and based on the numerous posts here, you can start later and still do well depending on your situation, doing due diligence, your risk tolerance and strategy. i was a little wary until I asked the original question on this post because it seemed like most of the podcasts were from 20-30 year olds or people that had started in that time frame.
I think I have to agree with your wife as I'd be a little leery about having strangers living in your home after being used to having a home to yourselves after all those years. I tried managing my first 2 properties that I obtained 15 years ago, but then got tired of trying to collect rents and handling the turnover and screening tenants that it wasn't worth my while as I was also working fulltime, so I got property management to do the work.
As far as notes and lending in an IRA, I was also thinking of that in that it may limit the possibility of being put in the situation where you run out of funds if you purchased a rental property as a buy and hold and needed extra funds to repair or maintain the property for whatever reason. Maybe I'm thinking of it too simplistically, but my line of thinking is that with purchasing a property in a SDIRA, you would have to ensure you had adequate funds for anything unforeseen since you can only use the funds in the IRA to make repairs or to contribute any funds needed for the rental property. With notes, it seems like you just collect the interest and if there's a default, you confiscate the property as collateral. Anyone have anything to add to this?