Flights to United States and Europe.
Fee Class EUA Lisboa Paris
Cancel / Change Economy USD 150 EUR 150 EUR 150
Business USD 200 EUR 200 EUR 200
No Show USD 300 EUR 300 EUR 300
Fee Local Value
Refund EUA USD 150
Lisboa EUR 150
Paris EUR 150

Flights to South America and Cayenne.
Fee Value
Cancel / Change EUR 80, USD 80
No Show EUR 120, USD 120
Fee Local Value
Refund Argentina USD 50
Uruguai USD 50
Guiana Francesa EUR 50
Bolivia USD 50

No problem, you can include more pounds at the airport during check-in. But attention, if the weight of checked baggage exceeds 23kg will be charged the excess of luggage.