Never, but never purchase any "Certified Pre Owned " cellular or electronic device. That word certified makes a person all happy and the terrible facts are and you can google it that those devices if not too cosmetic damage are simply reset to factory operating and then sent out to the poor suckers thinking all has been repaired and it will work like new.
Read many of the horror stories right on this forum about the CPO arrives and it works worse than the phone you returned.
I don't care what Verizon or any company says electronic devices and equipment is too risky. Look at the warranty given on these so called like new tested devices and products. 30-90 days and then you the customer are out of luck.
I just recently had a problem with my Samsung Galaxy Nexux. The USB port became very loose and the phone stopped charging when plugged in. My local Verizon store was very helpful in getting a replacement phone For Free!! And, yes I have the Assurance plan. Well the CPO I received by FedEx a day later wouldn't connect to the VZW network. After trying everything to make a connection, I returned this second phone to my local Verizon store two days later (now a Friday). On both occasions my wait time was less than 15 minutes. A reasonable time considering the number of fellow customers in the store. Well the technical staff confirmed the connection problem I was having and agreed to replace this second phone For Free!! But this time Verizon, for my trouble, upgraded my phone to an S 3 at no charge. My new phone arrived the next business day, Monday, and has worked flawlessly since. I have found that most of the time I feel Verizon is not interested in keeping me as a customer it is usually my fault for having unreasonable expectations. This recent experience has shown me that Verizon does their best to show their customers they care about keeping us around.