Never pay down a deposit in a bank account until you have met the seller, seen signed a purchase agreement.
No serious private advertisers ask for a down payment before you meet.
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.
Selling Steam Deck OLED 512GB with a glossy screen, bought about six months ago, rarely used, so I'm selling it. Battery 100%, all buttons and sticks work properly. The set includes the Steam Deck itself, a 2-meter charger, and the original case.