There is no fee.
You can leave questions or comments beforehand-- probably to help the leaders with the needs of sellers. (And to decide whether they need the extra-strength Stanfields or the super heavy industrial strength Stanfields.)
It looks like it will be text only.
And group based, which should make it difficult since the 'it's all eBay's fault ' folks will likely be out in strength.
Be prepared for a lot of irrelevant whining and screaming.