All charges are collected one-way per single flight. If passenger has connecting flight(s), the first boarding point will collect relevant charges also for all connecting flights (multiply all applicable charges by number of flights) until final destination (last destination to which baggage is through-checked).
Any passenger will be charged for excess baggage at the rates applicable for collection at the airport if she/he prepaid for excess baggage in the travel agency, but her/his actual checked baggage weight exceeds the limit she/he prepaid for.
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