Does tenant need to handle the small amount of landscaping outside of parking lot, for instance?  

Yeah, investing in the U.S. has enough challenges of it own.

Challenges?

Keep in mind that if issues arise and you decide to sue someone, it may be more challenging to take legal action against the wholesaler and hold them accountable for their actions.

If we were a GC and had cashflow for 2+ years and positive NOI they would consider a small business loan but outside of that, its challenging getting a business loan for real estate.

Basically his premise is nothing makes money like money and that's what creates wealth inequality.I recommend this Econtalk podcast interview with him, the economist host does not back away from challenging him.http://www.econtalk.org/thomas-piketty-on-inequality-and-capital-in-the-21st-century/

The only challenges you haven't mentioned is advertising for roommates, screening them and where to get a lease.

Pretty good from @Nathan Gesner too, BUT not 100% all the time.We know some turnkey companies that do NOT want to own real estate or are very picky about what they keep and sell the rest.It is a challenge making sure they are not selling you the property for MORE than it is worth.What country are you currently working in?

Property owners in Florida have faced significant challenges with squatters unlawfully occupying their properties.

My approach was to partner with a GC, so he handles the rehab estimates with his years of experience.Another option is to read J Scott’s book on estimating rehab costs.I've heard a lot about this book.