Is local market research just an exercise in futility?

You need to exercise good judgement and not be afraid in making your choices. 

I have a tenant that seems to always exercise this option. 

I don't yet know about the health of the seller but this could be an interesting exercise even if I don't purchase.

just a mental exercise on how could one accomplish this.... 

I have both, and have exercised both of them in combo (along with my 401k loan) to execute cash deals.

If you have a loan on the property, technically the bank can exercise their due on sale clause. 

The problem comes when a judge without the legal authority to do those things, nevertheless chooses to exercise his practical authority power and do them anyway.

@Joseph Denesowicz You're already renting it, just ask them to do a rent to own for a couple of years and exercise your option to purchase as soon as you have the cash and can qualify for the financing.

What are my risks of buying a property which was sold at a foreclosure auction to one party (who may have made immediate improvements) and then the property was taken by a party which had purchased/exercised  redemption rights.