NO - for the entire trip

I recently went through the motions of an ex-KRT DONE4 using the on-line tool (KRT-AMM-HKG-PER,BME-PER-DRW-PER-SYD-EZE-LIM-IPC-SCL-GYE-MAD-AMM-KRT)
YQ of USD309.08
plus a 'Tax description unavailable (SDEM)' of USD274.80 which may or may not be related to fuel fines

It should be possible to get YQ down to zero - say by booking on-line with a domestic AA segment as the first segment (so AA tickets) and then NO over-water AA flights and NO BA flights
And of course I'm sure if someone really wanted to - they could construct an itinerary where the fuel fines exceeded USD1000