How to read Property info on county website

[John Kernen]

Hi all, 

I spend some time driving neighborhoods and finding run down houses.  When I find one i am interested in i tend to go to my county assessors website and search the property.  Sometimes the values make sense and other times there is a value that is exponentially larger than the others. Like a house selling for $165,000 and then 3 years later it shows a value of 1,219,340...then a few years later another sale of 187,450.  I can't figure out why there would be a grossly larger # in between the 2 sales.  Also in the type column there is abbreviations I can only assume for the type of sale that it was?  Not sure what they mean though.  The Reception column also has a strange # that I do not understand.  Does anyone use these reports as a resource?  Am i wasting my time.  

On a side note, how does one go about getting lists of absentee owners and those that might be near default or have owed back taxes? I am just trying to figure out how to get my hands on the right properties that have the value needed to perform and rehab and have a strong ARV. Thanks!!