Bottom line, if it sounds too good to be true, it probably is.

Quote from @Arvand Sabetian: I think most others have already provided sound advice.I wanted to emphasis having a conversation with your tenants about the septic tank, not just a clause in the lease that you assume they'll read and understand.Many people are unaware of what they can be doing that causes issues to septic tanks (e.g., flushing the wrong items).Also, make sure you do a walkthrough yourself prior to filling the unit.

It sounds like most of your issues came to light during your due diligence.

Those gurus need to make themselves sound smart to get people to buy their courses.

I had a intro call with them on Friday and their business model sounds amazing, but maybe too amazing. 

You sound ridiculous.

I think my partner and I may be exploring a complicated solution - glad to hear that it sounds like one exists!

Sounds like a game-changer, or does it?

It sounds like a big win.

But you sound stressed (you should be) and without a way out.