Here is a magnificent 13c green block of 4 stamps showing a Canadian Army Ram Tank. The stamps are fresh, bright, perfectly centred and mint never hinged. The book value of the block of 4 stamps is $48.
I combine shipping. After the first purchase, I add 50c to each additional purchase if completed within a week of the first purchase. After you have completed your purchases, ask the seller to send you a combined shipping invoice to substantially reduce your shipping cost or wait until the seller has sent you the invoice. Make sure to pay the seller's invoice to receive the shipping discount. Do not pay the automated eBay invoice which does not reduce the shipping cost.