@Ed Mayo,I would take the county's advice and check with your attorney.All you likely need at this point is a locksmith (or a BIG hammer!) 

If you rekey locks for every new tenant for a 100  unit property, that can get very expensive.

I give all my residents a maintenance list with phone numbers of different handy types to call and I usually have 2-3 people from each trade they may need (24 hour plumber, electrician, locksmith etc.) on the list.

Rekeyable locks. 

I didn't expect that, while during the show, I was not sure about the original state of the door lock as people visiting the house might unlock the door from inside, so before I left, I locked it for safety When they arrived home, they immediately sent an email asking me return to unlock that door for them, then less than 20 minutes, they sent another threatening email saying that if I didn't return timely, they would hire a locksmith to break the door lock and I would be responsible for the fee.

You will need a locksmith to set-up the tree and key all of the locks.  

I also left a note saying I would be bringing a locksmith.

@Charlie MooreA lot of these comments about keeping money for things like rekeying, touch you paint, and carpets.... beware/good luck.

The first thing Crestcore did was to rekey the house, which is fine. 

Get your Preservation team together, locksmith, website and start looking like you can professionally take care of a banks Asset.