The extra premium will be for your account.

额外的保险费将由你方负担。

And the extra premium involved will be for your account.

此所产生的额外保险费应由你方支付。

As a rule, the extra premium involved will be at buyer's cost.

按常规，涉及的额外保险费应由买方负责。

And It is the buyers who will pay for the extra premium, I think.

我想这额外的保险费将由买方支付。

As a rule, the extra premium involved will be for buyer’s account.

按常规，额外保险费应由买方负责。

The extra premium arising from the coverage will be borne by the buyer.

由于保险范围增加而产生的额外保费由买方负担.

If you desire us to insure against a special risk, an extra premium will have to be charged .

如果你方想要我方投保其他特殊的险别，则须支付额外的费用。