When searching for an item to bid on, it is very important to be aware of the condition the item will be delivered in (new, rarely used, opened, commonly used etc), and also how the item is described on other websites that are not related to the seller's item description.
Go to google, and search your item and read about it. You could probably find opinion articles from current users and owners of the item you are interesting in purchasing. Compare this item with previous releases and future releases of it. For example, if it is a Samsung x660 mobile phone, find out about the Samsung x640 and also about later versions of Samsung phones such as the E530 and compare their features, maybe you will consider buying a different version, but if you don't, it's still good to know what features the current model of the item you wish to purchase contains.
It is also vital to ask questions from the seller, and as a potential customer it is your right as well as your privilage to ask as many questions as you like, don't be embarassed to ask silly questions because you will feel much more satisfied buying a product that you know very well, and others buyers will beenfit form your enquiries if they appear on the product's page. Don't forget to ask about any special offers on delivery the seller may offer. If the seller does not reply or his/her replies are too vague it is likely this seller may not be very trustworthy.
Remember to leave negative feedback to a seller who did not deliver what they described in their product page.