I am exchanging my Lenovo Flex 5 laptop, the parameters of which are ideal (a practical option), for your personal 250€ at the exchange rate in any currency. Belgrade. The reason for the sale is personal. All the best.
Never pay down a deposit in a bank account until you have met the seller, seen signed a purchase agreement.
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Receiving an email with an in-scanned ID does not mean that you have identified the sender. You do this on the spot, when you sign a purchase agreement.