At this time we have removed acceptance of third party credit card acceptance. You will need to have a card in your name or make payment via cash or cashiers checks.
A non-refundable fare can be changed at any time prior to the flight, but if not checked in prior to the flight closing, the non-refundable fare has no further value. You will need to purchase a new ticket to travel.
That depends on your nationality and factors such as how long you will stay. Visit our website page on passports and visas to find a link to live Visa Requirements.
The baggage allowance weight varies based on the airfare type and the destination you are traveling to. See this section of the website on baggage allowances by destination for checked, excess and carry on baggage.