There's nothing unbelievable. It is used computers in itself. Sometimes even the seller doesn't know what will happen if it is sold. Can only buy. If there is a problem, he can help you do it well. Besides, how much is a new computer? It's best to get a credit card installment, at least a newcomer.
Second-hand portable, it's good when it comes to good. People you know are most at ease. Buy second-hand if you don't know anyone. If you buy well, it's just your luck. I can't help it if I can't buy it well, because the two words are the most important, second hand.