On top of the obvious property-specific physical risks, there are many others.  

I have physical issues that prevent me from doing most traditional work. 

Simply having to physically get a check and show up to a location slims down your competition by a large margin.

When we find a motivated seller and agree upon a price and signing the contract, do I physically give them $100 to $500 in earnest money while I'm locking up their property for 40 days or do I give it to the lawyer office who does the title search?

Verify the tenants are paying tenants versus physical occupancy. 

It is 75% a people business and 25% about the physical real estate.

All I can say is the more spread out your buildings are the harder it is to physically get to them and time is money.. spending it driving between several SFH miles apart makes no sense to me..

I'll gladly exchange a few hours of physical labor to pick the brain of an investor with 25 years of experience (Lesson 2: Come from a place of service when looking to work with a mentor).After a day of driving, loading/unloading the truck, we were approaching home, when my investor friend mentioned that he was looking to shift a property out of a portfolio. 

Building relationships and trust take time and physically seeing the person I think helps.What question(s) did you ask to start a conversation about the possibility of them investing with you? 

I would like to see a physical therapist, dialysis unit or a primary care physician become my next tenant.