Hi. I'm planning to buy a second hand (used) Samsung Galaxy Note N9005. So I need to know how to check by looking at the phone (the way its screws are tied etc) whether the handset is repaired or refurbished? Are there some specific indicators to gauge that? Actually, the shopkeepers here try to sell repaired/refurbished phones in the name of original and 'never repaired' handsets so I need to know about it. Also, what specific functions I should check in a used phone before buying it? Any help will be highly appreciated. Thankyou.