I am thinking of purchasing it at his asking price, then lease-optioning it to another tenant-buyer with a non-refundable down payment of 40K with the option coming due within 3 years (maybe up to 5, with extensions).  

I share the properties between the providers and can gauge their performance and price.The responses are great and they cover items within the infrastructure such as AC/heater,electrical, plumbing, garage door etc.If there is anything uncovered that needs to be fixed, my broker connects me with local handy men or professionals to take care of those issues.One of the providers, https://www.ahs.com/ charges $75 per call. 

@Bill Gulley has written extensively about Subject to existing financing if the loan is calledIt has to be a wonderful house to do sub 2Be prepared to get alternative financing if the loan  gets calledExit is usually renting or lease to own

Problem was the tenants never stayed long enough for the investment to truly perform like it should.

It seems like all plans being pitched can be described as diversify into the stock market & mutual funds, or buy annuities and pay someone 1% of my net-worth annually regardless of performance.

I would highly discourage contacting them frequently if you don't have business to perform, as this could cause you to be ignored and labeled as a waste of time.

I love the idea of offering my time to perform open houses for other agents in my market in order to practice my communication with clients, build my own leads list and just to get my name out and network.  

My question is how do they perform the due diligence to check out a property to determine if it is a worthwhile investment ?

I'm sure there are other options out there that include corporations, etc. but my gut says that you're really stretching here and there isn't a benefit to what you're trying to do.

I am in the middle of a deep rehab on another property; 2 SF vacancies + getting into a new deal might stretch things a out of my comfort zone.