I'd like to research these IRL and think that I should start at the county records offices. Plus any hints on possible costs associated with purchasing said properties.

You local tax assessor's office should have all the answers you need. As far as costs, there really isn't that many ancillary costs besides paying the tax lien amount. However, the possibility exists that there might be more than one lien on the property, and you would be responsible for those, after you acquire the property. Do you due diligence before buying.

Hope this helps…

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