Shipping and import cost jumped drastically after placing bid?

[marcfernande-9]

I placed a bid on a used item and before doing so the item's calculated shipment cost was about ZAR 550. After placing the bid it jumped to ZAR 13000+. How does this get calculated? I had to cancel the bid almost immediately after seeing this because that is an absurd amount considering I can get the same item(Brand new) locally for less than half the of the shipment and import cost. This item was in the UK and I stay in South Africa.