Final Value Fee on Shipping is Unclear and Poorly Defined

[caribou_antiques]

This final value fee has become very frustrating to me as a seller.  Not only because it adds to the already high fees associated with ebay, but also because the exact methodology is not spelled out clearly by eBay.  

Here is my typical scenario:

I sell rare antiques and collectables.  These are not your run of the mill things, most of them are real antiques (over 100 years old), with real historical value.  I also sell some collectibles and antiques that are quite common as well and this is because I buy large collections at a time.  So many of my items are very fragile or require special shipping requirements so I normally charge a fixed price.  Now this fixed priced is typically an underestimate and I will lose money about 70% of the time.  On the rare occasion I over price shipping I will refund it no matter what.  Today for example I charged $35 on an item and ended up paying $50 on shipping. So my point is "the final value fee on shipping" is very unclear and if EBay wants charge this it needs to be spelled out more clearly.  

I want to see the calculation for this fee. Is it based off price? How does eBay know what the best shipping is for an irregular shaped item?  How is insurance on the item figured into the situation?  The majority of my sales are well over $1000 and I have to charge for insurance!