Chicago Agent has an article on how to navigate borrowers though financial preparations for a short sale appointment.  As the article notes:

Even though you are already calculating the list price and quite possibly the commission, this may not be the meeting where you lay all the cards on the table. And, for this very same reason, it is often difficult to go through an almost insurmountable number of items that need to be collected and discussed in one fell swoop.

The article provides four specific areas to be ready to address.