After years of standing on principle and "I am right"...I finally listened to what some really successful people do (in all walks of life): fix the problem and move on! 

But the acronym BRRRR stands for Buy Rehab Rent Refinance Repeat.

@Justin Silverio You posted TLO for skiptracing  What does TLO stand for ?

Write down addresses, look up the owner info and mail them a letter that will stand out in the crowd.

The only guy I have seen stand the test of time is Todd Dotson. 

Do we have legal ground to stand on here?

Should take a few days, make a few threats and cross your fingers.If you didn't use a realtor, I'd suggest calling the previous owner and letting them know you don't want to get lawyers involved but this can't stand.       

@John Hixon, I neglected to consider that the tenants may not stand for the rent staying at $850 if they no longer have an electricity subsidy.

Like I said, I do not have a ton of experience in tax liens,  but I know that you will want to at a very minimum drive the properties that you intend to bid on and make sure that they are standing (not burned to the ground) and not condemned. 

This does not include management, budget 10% for a good one on a stand alone. 4% might be generous on a multi like this, I'd budget for closer to 5%. 25% down might get you a little better rate.