BTW, we use TLOXP from trans union for detailed backgrounds, plus Google, Facebook, and other social media.

To run a credit and background check on SmartMove (BiggerPocket recommended), the applicant must provide a social security number.

Craigslist isn't sufficient - he needs to be leveraging Zillow, Apartments.com, Facebook Marketplace and his own social media presence. 

In higher end rentals you tend to get a higher income more stable renter, one with steady employment and social responsibilty.

What economic and social indicators should I look for?

A local attorney must be engaged for more specific advise.As for the specific case of whether the fact that there is an insurance policy which insures 2 properties, one in the name of the individual and one in the name of an LLC, where that individual is also a member of the LLC… I would not say that this circumstance by itself would be sufficient cause for piercing the corporate veil, there would need to be more reasons than just this.

Do you guys personally feel that tax liens would be a good endeavor to engage in while I am at college?

More of a social mixer, but would love if you could make it.  

There are a few living legends around; Jay Decima, Peter Fortunato, John Schaub et al and I suggest that readers make a social point to hear them while they're still actively speaking (and breathing).

Have you engaged in such a campaign as of yet?