Lastly in taking the CI training we soon discovered that it is a gigantic sales pitch for more money and products that are never delivered.

I like to be up front - personally.

In addition, they will need space in the common areas for their stuff as well (think refrigerator & pantry for food, etc.)No background check will show how clean they are, how they respect your space, whether they are a loud person, or a night owl, who they invite over to stay with them and such.  

As we're running out of personal capital to continue acquiring with, we're exploring a structure where we give investors an 11% preferred return that we buy them out of in 7 years.

I've made many great connections, educated myself on topics I didn't know existed before and have taken actionable steps in my personal investing business that I wouldn't have done otherwise. 

Has anyone tried the All-in-One first-lien HELOC product?

The questions you are asking are far to vague for anyone to have major input or guide you correctly as each person's situation is different. 

You aren't the first person to suggest it, however.

@Kiefer Cheney your best "farm area" is your personal network!

@KiKi Wood Is your person for STR set-up in Indianapolis!