How do you get money from your account to any patent offices bank account across the world with certainty of them receiving the correct amount in various currencies as cheap as possible?
In most countries, it is mandatory that patent applications are filed by patent attorney or agent registered in that country on behalf of inventor. For those countries means of payment of fees from 'your account' is purely academic. What @ DonQuiKong has said about payment procedure is right.
However, few countries like the US, India allow filing by inventor himself. For those countries, one can pay online by credit card. Correct amount is paid since, amount to be paid is calculated by the office site before payment. I have always found the correct amount has been credited to official account immediately. Your additional fees are credit card fee for the transaction which you pay after billing.