Can I include the ebay fees on postage in the postage I charge a buyer?

[antiquedolllady]

I have just been in dispute with a buyer. Firstly she asked me to pack an item in a way that increased the size of the package (a very large doll she wanted sitting in a box rather than lying down). I clearly stated the posatge cost in my listing, but she is sending me emails complaining about the cost - now that I have just posted it to her. I estimated the cost correctly (Over $20) - but she keeps on telling me it should have cost less

I made the costs absolutely clear to her before I posted it (via email), and said I would charge $5 for packaging (becuase it was a big item and that was my actually cost of bubble wrap). I have charged her the actual postage + $5 for the wrapping.  I also charged her the ebay/paypal fees on the postage,  

I just wanted to check that ebay policy allows me to actually charge their own fees on postage (as this forms part of the actual postage cost) .  I don't include it in the item cost because this would then make it more expensive for people who pick their item up or who live close by.

I am concerned this person will give me negative feedback.. I have repeatedly asked her what she wants me to do about it - but she does not give me any meaningful response.