If we are buy 2 nd hand mobile we dont fall on the words of the seller.
First we wants to select a price range.after that you please ask to show phones under that price range. And check the phone that you are like by appearance. And use its almost all feature. You must take care to check sound clarity and the all offered features are on work. Camera , gps, finger print senser etc. Because we dont able to know such feature under external inspection.
And selecting a phone we must take care to select best campany. That is there must be available service centre and good customer care support.
Thank you.