Yes we declare full value. We are required by US law to declare full value on all international shipments. It is also ebay policy to declare full value. Knowing all customs laws, rules, policies and fees, is responsibility of the buyer.
(Always try to tell them this in the most polite/courteous manner because most of them will get mad and try to make it seem like it is our fault or that we tricked them and then act like we owe them something. Also, tell them that we can refund them for their order and cancel it if they do not want us declaring full value. Here is the attached eBay rules and our shipping policy where it says that we have to declare full value. Feel free to link customers to this.)