Sites such as eBay are extremely useful for finding that wonderful collectable, part or a multitude of other things you've been meaning to and wanting to, buy for yourself.
Sadly however, as with many other sites, there are those on these sites, that are doing as much as possible, to part you with your money. There are millions of legit users on there, just like yourself, but don't forget - there's also scammers and other questionable people on there, and unless you read things properly before bidding/buying, you could end up being stung.
For example, you wouldn't be too happy if you bid on what appeared to be a very cheap laptop, only to note when it arrived, that it was actually just a photo of the laptop (the familiar "exactly as pictured" scam).
Similarly, finding that great product that appears to be at an unbelievable price. I came across one such product a couple of days ago. A twin Makita drill set, with case and battery etc, that appeared to be extremely cheap at only £7.50 - then I noticed the postage - and very unbelievable £65.
I reported it to eBay and it appears, since then, the reason for this, is because the person selling it on eBay wants to try and scam eBay out of some of the fee's they'd have had to pay had they sold it at the "normal" price (i.e. £65 for the drill set, and £7.50 for the postage).
eBay charge fees for selling things, so they can keep the site running, so trying to scam them out of part of the fees, by using practices such as this, is hurting not only eBay, but you - the user.
A different listing I came across the same day, offered what appeared to be a great collection of furniture, at a similarly great price of just £99 - but when reading the actual product details, you found out you weren't buying the furniture shown in the image - the image was actually just an example of things the seller had allegedly created.
I could ramble on about the various different scams and scammers on eBay, but you'd end up getting bored inside of 5 minutes, so to keep it short, the lesson here, is to ensure you read not only the products details - but the postage costs. It is also VERY important that you read the sellers "feedback" (click the numbers shown in brackets next to the sellers name), as this will tell you whether or not you can trust the seller.
If you see a listing using methods like this (excessive postage, or claiming to sell products when infact, they're selling "services"), or anything else, ensure you report it so eBay can take action.