I've just got fresh information for you from my Iranian friend. According to new legistlation done by Ahmetinejat government, they give you a card or something like voucher. This voucher allows you to get 50 L. petrol for $0.20 per liter. After that you have to pay $0.80 per liter. World is changing so does the Iran. No more cheap petrol.
However, he (my friend) told that things are changing very fast in Iran, so no one knows what gonna happen after 10 days.
But this is the situation for now. Hope this helps.
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