They "safely" guarantee themselves decades in the rat race by failing to use leverage. 

They then have the right to foreclose and take back the property if you fail to meet your obligations." https://www.biggerpockets.com/forums/50/topics/148955-seller-financing-what-happens-to-the-deed-title

Without fail, you call them and the rate is something atrocious that you can't cashflow with, and they typically have prepayment penalties, meaning you can't refinance out of it (or sell) for several years, or if you do you face a steep penalty. 

What if your plan fails, is plan B to back out and do you expect the refund of your EM?

The main reason I do not participate today is my local plan administration is slow, taking 2-3 weeks to schedule the initial inspection, then if something--even a very minor problem--causes the unit to fail it takes them a week to re-inspect. 

my dad sold most of his paper in those days.. so we just wiped out the PV calculator and backed into what our note buyers would pay for the given cash flow.. that turned out to be 30 months zero interest has the same note value as a 7 year 15% rate note.. shocking I know.I have employed this over the years to sell my OREO s that I foreclosed on buy and hold investors who failed. 

I think part of the difference is you are buying extremely distressed loans and borrowers file BK for foreclosure protection and most will inevitably fail.

If my purchase whether a rental or a flip fails in either a small or spectacular fashion will I be honorable enough to admit I made the decisions and not my Realtor ?

You will fail.

One of the potential members has a substantial lien against him for failing to have auto insurance during an accident.