pennyblackie, this has happened to me also. A couple of years ago I won two lots from a certain eBay
seller. I asked for an invoice with combined normal shipping and received it with what I knew was too high a charge. I queried this with the seller who told me I was paying for Registered Post due to the high cost of the two sales.
Sure enough, having paid A$8 for postage, the two lots were sent by normal post (cost A$1). As you'd expect, I received no response to my questioning the overcharging from the seller so I opened a case through eBay
. Within a few days I received a message from the seller saying despite what he had advised he was refunding the overcharged postage. How very magnanimous....
If your intention is to keep the item, push hard for the refund of the overcharge, leave negative feedback honestly describing what has taken place, don't deal with that seller again and move on