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.
Sublease the apartment for the period from June 27 to August 28 with a contract. 1. 34 m2 2. Belgrade, Kanarevo Brdo, Ivana Michurina 15 (20 minutes from Slavija) 3. Two folding sofas, a small balcony 4. 350 euros per month + utilities and internet (~50 euros per month)
