My hope is I can gain their trust as a property manager and eventually be the one they turn to to sell later on or refer for business in the future.

That's not what I am referring to.

Don maybe referring to state of Texas were lease options are highly regulated.. just sayin..

There are other ways to determine rental amounts like researching in zillow and/or rentometer, which I typically reference.

You are referring to this article?

Quote from @Jed Butikofer: @Henry Clark When you say Texas property tax sales are you referring to land flipping?

-------------------------------------------------------------------------------------Recommend exploring as many sources as possible to get referrals AND cross-reference them to get as much accurate information as possible.Check out NARPM.com, BP’s Property Manager Finder (BiggerPockets: The Real Estate Investing Social Network), etc.Also, encourage you to learn from the mistakes of others - by reading posts here on BiggerPockets about owners not having their expectations met by their current Property Management Company.

Happy tenants are more likely to renew leases, take better care of the property, and refer others.

I'm guessing you got the same letter I received from REVA, although mine was in reference to a different DST - Reva One. 

Find a reliable Realtor, as they can refer you to other key team members.