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When buying an item on eBay, make sure that you have thoroughly researched the item before placing a bid. Look up the market value and search for similar items on auction and watch what prices they're selling for. This way, you will get a good idea of the going rate for a particular item, so you will recognize a genuinely good bargain when you see one. Take the time to do your research and make informed decisions before buying.  Just imagine how angry you'd be if you rushed into purchasing a watch for $50 (thinking this was an excellent deal) only to see the same watch sell for $30 a week later. Whatever you do, don't rush into a purchase just because you think it might be your only opportunity to buy - with the exception of very rare collectibles, most sale items will pop up again and again on eBay. Once of the most important things you need to consider before making a transaction on eBay is the feedback rating of the seller. The efficiency, openness and trustworthiness of the seller can make a huge impact on whether your buying experience on eBay is positive or negative. Each seller has a feedback score, which they receive based on the reviews of eBay customers who have previously bought items from them. This information is available on the description page of the item to be sold, in the top right hand corner.  Whether the seller's feedback rating is good or poor should inform your decision to buy the item. If the rating is poor, you buy the item at your own risk. Though uncommon, it's possible that the seller may ship you a broken or faulty item, or fail to send the item at all. You can also read reviews of each seller on their feedback page, written by previous buyers. This will also help to give you an idea of what you can expect when buying an item from them. To save time and hassle, it is important that you read the description of each item very, very carefully, to make sure it is exactly what you're looking for. Some pictures or titles may be deceiving (whether intentionally or otherwise) and you might be fooled into buying the wrong thing. Make sure to read the entire description thoroughly, looking out for any mentions of flaws or problems with the item.  Remember that if you are disappointed with the condition of your item when it arrives, even though the flaws were clearly noted in the item's description, you will have no one to blame but yourself. In this situation it might be very difficult to arrange a return and the seller will not be happy. Examples of things to watch out for include whether the item is new or used, whether it comes in its original packaging, and whether it includes any necessary extras (batteries, chargers etc.) Be wary of very vague or confusing descriptions, as there is an increased risk that the item will not be what you expect. Shipping fees are another expense you will need to factor in to the cost of buying things on eBay. It is very important to check the cost of shipping before you buy, as many buyers get caught out by very low selling prices which are balanced out by exorbitantly high shipping rates. For this reason, you always need to factor shipping costs in to the total price of your item. The shipping information should be stated clearly beneath the selling price of the item.  If you are not satisfied with the shipping charge on the item, then you should not bid on it. It is very unfair on the seller to commit to buying the item, then refuse to pay high shipping charges. If you really wish to find a compromise, message the seller before agreeing to buy the item, to see if a solution can be found. You also need to check what location the seller is shipping from and where they are willing to ship to. This is particularly important if you are buying from an international location, as some sellers will refuse to ship outside their own country. This information is available underneath the shipping costs. Good communication between the buyer and seller can transform any buying experience from poor to excellent. Most high-rated sellers will be very responsive towards any questions or queries you might have about the item itself, the shipping method and fees and the payment method.  In order to message the seller, scroll down the item page until you reach the "Question and Answers" box beneath the item's description. There will be a link titled "Ask a question" which you can click on to message the seller.  You should make sure that you have all of the correct information about the seller's preferred payment method and return policy before making a purchase. If this information is not supplied on the item page, ask the seller directly. What many new buyers don't realize is that by clicking on either the "Buy it Now" or "Place Bid" button, they are committing to purchasing the item and there is no going back. Once you hit either of these buttons, the seller is automatically charged a fee by eBay for their use of the site, so they will not be happy if you try to back out of the sale.  In some cases, the situation can be resolved if you have a legitimate reason for backing out of the sale and you message the seller immediately requesting a cancellation. You may need to cover the cost of the fee they've already paid, but at least you won't be forced to buy an item you don't want. If you do not have a legitimate reason for backing out of the sale and simply refuse to pay for the item, the seller is entitled to open a non-paying bidder dispute against you. This may result in an unpaid item strike being placed on your account, which will deter future sellers and buyers from wanting to do business with you. If you get three of these strikes, eBay will suspend your account.

Summary:
Compare the price. Look at the seller's feedback score. Read the description carefully. Look at the shipping fees. Message the seller if you have any questions. Don't click the "Buy it Now" or "Place Bid" button til you're sure.