How does the Inventory item look now?  Is the Average cost OK?
 
I had no complaint with the job cost report ... It looked good.
 
My complaint was the last cost and average cost were negitive numbers.
I can (remotely) understand last cost as a negative, but average should never be negative.
 
Given the purpose of the Last Cost field, and the fact that it is mostly informational, I don't think
it should be updated with any negative results.

I must have a setting set differently than you.
I am going to review all my settings that have to do with WO's and see if one jumps out at me.
 
Can you think of any settings that I may have different that would affect this function?