Let's assume the value of the property hasn't changed and is either quit claim or warranty deeded right after the first recording. 

But some are move in ready and valid comps for the turnkey offers.  

This deal allows 3 exit strategies:  #1: you can sell the property after 12 months.  12 months is the cutoff time so that the IRS doesn't categorize you as a dealer and allow you lower capital gain taxes   #2 You keep it as a rental for truly passive income as long as it cashlfow  #3: if we hit high inflation or increased inflation, you have a second gold mine because you are causing "inflation induced debt destruction"  Jason Hartman told me about this and I thinks its totally valid.  

Conversely, if a house is well-below, you may consider selling (or getting a home warranty) before the big ticket items start failing. 

I leave it up to the other members on the forum to validate how viable this would be in Nashville, but it's just a thought. 

But we also had a case where we had title insurance from a company and later there was a potential claim, and the company had gone out of business so the title insurance was no longer valid. 

Use a Warranty Deed, not a QCD.

Minnesota has also build a new public train which just opened a month ago to the public, I'm guessing this will bring value to the areas it operates, is my thought process valid?

If you encounter resistance, a nuanced interpretation of the statute can push that time out to 3 years.There are services that will verify the validity of the tax sale for particular providers of title policies in lieu of actually filing suit to quiet title.  

Your concerns are valid.