The best way to learn about how to really invest in real estate is to read books, listen to good podcasts, and pair that with going to in-person meetups so you can see people just like you, married with 3 kids, who are making it work for them.

Unrelated persons ordinances are common. 

I don't know a single person affected by tornado in Dallas while we have had them and I have seen the destruction.   

Would the person who takes on more labor to repair the property have greater preferred equity or is this usually treated differently?

I have also utilized owner financing for longer periods of time, including personal residence and 2 barrier island houses on the coast of Florida.  

Focus on the person (the seller), not the offer.

Usually my time spent with newbies last a minimum of 1-2 hours on our first meeting (either in person or on the phone).  

The loan does need to be secured by the property being improved if we are talking about a personal residence and personal itemized deductions on Schedule A.

Until you see the property in person the numbers are completely meaningless unless you have a working relationship with that listing broker for years.

It is regulated and you need to learn the law before accepting any funds from another entity (person) in a syndication.