You also has to pay attention to exchange rates. Are you being paid in US dollars, but converting into Euro? Than you are making less money than actually stated in your rates. On the other hand, if your local currency is less valued than the currency of payment, you will be earning a bit more (not so much, don’t be so excited).
Also, take taxes into account. What can be deducted? How are you going to keep track of your payments? With Paypal, you can download the year history, which makes completing the Brazilian form much easier. You can also add Paypal fees to deduct as a cost (check your local rules for taxes). The same goes for your bank account. Are you planning to use an accounting service or do your taxes yourself? Remember that any expense you might have with getting paid must be shared with your client when you agree on a final rate.
Whenever payment is involved, you have to be an expert in Math (at least this basic plus/minus/times thing). Learn the tricks and define your lucky number. Then, be free to do what you like the most – translating!