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 a children's toy "Doctor's kit". Cons: broken lock. There are other toys, books, puzzles for children up to 5 years old - write private messages.