I believe the listia rules state cover exact expenses. Which include-But not limited to- shipping cost, insurance on the parcel, extra packaging or wrap, etc... It also states it has to be reasonable.
Using a large USPS FREE priority box is only 12.95. This would fit in a small box. I wish new members would realize that offering free shipping for their first few auctions gets them a lot more credits, and a good reputation. I would bid way high on this if the seller had an established and trusted rep.