I have made up the similar sentences below.
(1) I'm sad that I have to pay a $200 customs duty on my online order.
(2) I'm sad that I have to pay an customs duty of $200 on my online order.
(3) I'm sad that I have to pay $200 of customs duty on my online order.
(4) I'm sad that I have to pay $200 in customs duty on my online order.
I'm not sure about the correct way of saying "$200" and "customs duty" when they are put together. Please help me. Thanks very much.