Bidding websites are awesome. You can bid for new or used things and get them at a fairly cheap price. Far below the retail price. And not only can you bid on items, you can sell them too. If you have old items that you no longer use; you can can sell them on these bidding websites. People will buy almost anything that they are looking for. You will be surprised. And if neither of these options interests you; some sellers will be willing to trade items for an equal value.
eBay is currently the number one rated bidding website on the internet. You can buy, sell, and trade items on this website. The best thing about eBay is that it does not just exist in the USA. eBay is stationed all over the world. You can sell anything from a twenty thousand dollar diamond ring to a two dollar pair of tube socks. They also have a column where you can buy cars. This is called eBay motors.
Another good website is Craigslist. They also buy, sell, and trade items. But the best thing about this website is that they offer services as well. Be cautious with this because some of the services are highly illegal but Craigslist is working on erasing these illegal services. So people can have a trustworthy, safe, fun experience on their websites.
There are other sites to bid on like ubid and bidz but these are just a couple that came to mind. There are also many more than this but these are the top sellers in the league right now. Of you are ever interested in buying, selling, or trading items; I think these websites would be a great start.