Don't trust people on OLX

A guy named Artwell McKenzie contacted me in regard to an olx advert for my Xbox 360 Elite. I told him that I wanted R2500 for it and he agreed to pay. He \did"an Internet transfer and sent me his proof of payment in addition to the text I received from Nedbank. I thought that this was proof enough and agreed to meet him. I gave him the Xbox knowing that the transfer would only reflect on my Standard Bank account in 2-3 days. The amount has still not been received and it has been a week. Obviously Artwell McKenzie won't answer my calls and texts. I recommend that before selling anything to people on OLX or any other Internet based buying and selling site make sure that you received the payment first. """