The auditor literally took each property apart using the detail accounting we had on each ledger for each property.

I don't see how they could audit or investigate.

We recently wrote a letter to the Tax Auditors office to request a re-assessment of the tax value on one of our properties.

I will also be submitting the same appraisal to my county auditor to help lower the taxes.

If the county auditor discovers within three years after the date of the sale that a parcel was sold to that owner or a member of the specified class of parties connected to that owner for a price less than the amount so described, and if the parcel is still owned by that owner or a member of the specified class of parties connected to that owner, the auditor within thirty days after such discovery shall add the difference between that amount and the sale price to the amount of taxes that then stand charged against the parcel and is payable at the next succeeding date for payment of real property taxes.

You do have to register your property with the county auditor though.  

Find a home that you are interested in, look on the auditors site for sale history.

I thought it was an REO because the auditors site said JP Morgan Chase owns it.

They are usually triggered during an audit or if you change the insurance policy, that's why I usually recommend keeping the existing policy under the seller's name and adding your new policy on top. 

I think that was a little literary freedom calling auditors "PI"s.