Buy a cell phone for the correct carrier and technology
This may sound simple, but many customers have come to us asking why the phone we advertised for US Cellular or Sprint PCS does not work with their Verizon Wireless service! Obviously, it would be wonderful if every phone was automatically compatible with every carrier, but this isn't how it works. If you have Verizon, you need to search for phones that will be compatible for Verizon. The same principle applies to Cingular, Alltel, AT&T, Cellular One, Sprint PCS, Cricket, NTELOS, Unicel, and Midwest Wireless.
It is also important to buy a phone with the right technology for your carrier’s network. There are several main types of cellular technologies including CDMA (Verizon Wireless, Sprint, US Cellular, Alltel, Cricket, Cellular One, Midwest Wireless, NTELOS), GSM (Cingular, AT&T, T-Mobile), TDMA (certain regions of AT&T and other carriers), and iDEN (Nextel).
GSM and iDEN phones use SIM cards, the other technologies DO NOT use SIM cards.
When buying a GSM phone you can buy one that is "UNLOCKED" for use on ANY GSM carrier, or you can buy one that is labeled for your carrier. It is important to note that even though AT&T merged with Cingular, the SIM cards aren’t interchangeable unless you have an UNLOCKED phone. It is usually a little bit cheaper to buy a GSM phone that is only for use on your carrier if you do not need the features of having an UNLOCKED phone. After purchasing a GSM phone you simply insert your SIM card and it is ready to use!
Determine what features are important to you in a used cell phone
Do you simply want to replace a broken phone with the exact same model you had before? If so, type in the model number and you will likely find exactly what you are looking for. However you might want to upgrade to a camera phone, a flip phone, or a phone that can be used with a Bluetooth headset. If you know what features you want, do searches for various features using eBay’s item specifics to find exactly what you want. Keep in mind that if you won’t use the camera function or built-in MP3 player on a phone, there is no reason to spend extra money on a model with those features. You would probably be just as happy with a basic flip phone.
If you want to know exact details about features of a phone, you can type the model number into Google or visit a site such as PhoneScoop to view detailed specifications and features.
Cell Phone ESN
A phone's ESN (electronic serial number) is a unique identifying code that allows the cell phone network to communicate with the phone. This number is printed on the back of each phone and can be seen if you remove the battery from your phone. Until a phone's ESN is registered on the network, it cannot make or receive calls. In our experience, Sprint PCS is the most fickle about activating used cell phones. For some reason, the ESN's of many used phones come up as "lost" or "stolen" in Sprint's system, even if the seller has acquired the phone legitimately. We have had customers call Sprint and been told that a phone cannot be activated, however if they take that same phone into a Sprint retail store it can be activated with no problems! Unfortunately it seems that the success of activating a used phone with Sprint can depend on the knowledge and skills of the customer service representative you deal with!! Other carriers such as Verizon Wireless and US Cellular don't seem to have as many activation issues with used cell phones as Sprint does.
Read the item description and look at photos CAREFULLY
Used cell phones can vary dramatically in terms of cosmetic condition. Some used phones can look nearly brand new and others will look like they have been chewed on by a dog or small child. Many sellers use STOCK photos (the same photo for each phone of the same model). Some sellers use a scaled rating system (1-5 or 1-10) for the condition of their phones; however one person’s "2" may be another person’s "4". It is your responsibility as a buyer to make sure you read the item description carefully to get details on any cosmetic wear to the phone.
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