Here is what I have uncovered from reliable sources : The inventory in Indy has gone from 14K in 2012 to 10K in 2016, that is still a ton of inventory.

The stable and reliable flow of income is a key consideration in mortgage loan underwriting.

If you know students, or if you are going to grow into knowing more and more students, you could have a steady flow of reliable tenants for the time that you live there.  

There are no reliable sources for cap rate comps for 4plexes. 

I have found rent-o-meter to not be the most reliable site.

Only reliable contractors who show up, meet timelines without excuses, and know the local permitting and codes need apply.  

And I couldn't find any reliable contractor who show up the last 2 weeks, seems they all busy.

I would use a reliable 3rd party property inspector for this which will cost you about $200 - $400 based on the size property.Before doing that, definitely have a local realtor that's representing you look into it.  

I know Redfin and Trulia are not reliable, but I looked up the address and found a value.

I am a broker...I can tell you, at least for our market (and I know other brokers outside of our market say the same thing), there is no reliable 3rd party data.