Let the broker know you will be representing yourself and not be represented by an agent. The MLS co-op is being advertised at 3% however all commissions need to be authorized by the lender since it is a short sale. you can use that 3% as a leverage point.
Preforeclosure is a generic term without precise meaning other then a NOD has been filed. Whether a NOT (notice of Trustee Sale has been set or not) will be up to you to find out. Similarly finding out the status of where the seller is with respect to getting things square with the lender for the short sale will be up to you.
Just to be honest with you, there will be no chance whatsoever that the lender will accept your offer. They only reduced the price on 6/13. I have also seen some cases of short sales advertised and not accepted at offers IN the price range. I do believe that is absolute stupidity by the lender but that is the way it is right now.
Anyways it is a good exercise for you to go over there and start to learn the process more.