Ebay does not permit sellers to charge for insurance separately.  It is to be included in the shipping and handling chares.
http://pages.ebay.com/help/policies/...practices.html
	Quote:
	
	
		| What you're not allowed to charge 
 Insurance: You can't charge a separate fee for insurance, although you still need to make sure your item arrives as described.
 
 Tip: You should incorporate any insurance fees into an item's price or handling cost.
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 So to the OP, what the seller is doing is directly in violation of ebay's policy.