Why do post and packaging cost so much?

How much does packaging tape cost at the post office?

I purchased a camera from E Bay and it was free package and postage but had to send it back as it was faulty. I had to return it by registered post and it was costly. Am i responsible for the cost of returning this item as how was i to know it was faulty...

o.k another daft one i know..if you could buy bubblewrap filled with a gas thats lighter than air..say hellium for example..would it make my parcels lighter to post and therefore cost less to send them...or maybe fill the boxes with balloons filled with...

If it adds any help the jeans are a 28" waist and a 32 leg and the url of the product in which i am going to buy is, http://www.play.com/Clothing/T-Shirts/4-/10136678/Voi-Men-Mexican-32-Leg/Product.html#

I'm selling my ipod and need to post it to West Africa, I still need to find out what country though. Anyway, I don't know how much it is going to cost and was hoping I could check online so I can let the buyer know but I'm confused on what links to...

Hi, I have 82 DVDs to sell on Ebay. They are selling at around 99p each. I have worked out that it costs around 65p to send a DVD of in a jiffy bag by post. I also have to buy jiffy bags which will come to a total average of around 80p for Postage &...

I want to sell this computer on eBay, but how do I figure out how much the postage and packaging will cost without dragging it down to the post office?

Does it mean post and packaging calculated in the price of the item so we pay no extra on post and packaging? Xx