Not investors per se, but more of the people that have rental properties more by accident than design. 

And, we’ve done it all as long distance investors from SE Asia where we serve impoverished families in our clinic.

I’m in SE Iowa.  

Business = ordinary rates + 15% SE tax.In case of a rental, you owe capital gain taxes on the 20% of the $30,000 down payment.Both scenarios above are over-simplified.

And while we don't "mentor" per se, we do work with new Investors who are actively marketing for leads.  

So I would say, no, I would insist, that though your buyer may have had issues getting the predicted ARV, it is not because we were wrong per se, but because of one, or some, of the many other issues, totally in your buyers control, not in ours, that arise throughout the life of any project.

I still suggest you and your borrower se an attorney.

It took about 5 sit-downs of 4-5 hrs.I had to pay a significant SE tax, so my wife convinced me to use her CPA.

I also like Solo 401(k)s more than SDIRAs, but you should be able to reduce income tax with either (but not SE taxes). 

I live in SE PA so if you need anything feel free to reach out and hopefully I can help!