Marketing To A Tax Delinquent List

[Sydney Chamberlain]

I just grabbed the tax delinquent property list for my county and I am considering doing a direct mailing campaign to the property owners. However, I have a couple questions about due diligence. 

First, if an owner gets back to me, do I reach out to a title company (or someone else) to learn about the liens, mortgages, and potential amount owed on the property? 

Secondly, could any experienced investors let me in on some of the criteria they use to value a property? Is it just the amount owed and then some? 

Thanks in advance :)