Postage + Listing Fee = Cost of sales?

Evening all,

Just a quick question that has dumfounded me somewhat! I previously posted a thread concerning a friend whom was going to do an ebay shop aswell as being a sole trader, now they have sold their first product. Through ebay you have to pay a listing fee aswell as the postage my question is does this figure go into the sales day book as a debit which then be known as a cost of sale located at the top of the P and L account or do we create postage and insertion fee expense account? I think it will be classed as cost of sale, though a friend thinks itll be an expense account......any advice?!

Thanks all x