The fare you see on AA.com contains all the YQ you will end up paying.

Obviously people on this board chose AA rather than the competition. I personally chose to focus on AA/Oneworld rather than Star Alliance in part due to less that satisfactory flights to and from Japan with AC and UA.

I believe you will have to clear US customs in Chicago or New York even though you won't leave the airport in the US. The AA flight from HND to JFK is also poorly timed so you may want to come back from NRT even if you fly into HND.