I wanted to share my experience with an online service called Flystein. Basically Flystein is staffed by experts in booking international air travel. You pay them a fee and they will search and search to find you the best flights using every available trick in the book. Unless you are a a regular international air traveler or have a passion for booking air travel, I highly doubt you will know about all of the strategies and options that they have and use. They don't actually book your travel for you but find the best options for you and then it's up to you to book. I am traveling summer 2019 round trip to Japan on a trip-of-a-lifetime with my daughter. I have American Air vouchers and miles to use. Flystein looked at my dates, my budget, the vouchers, and miles and gave me some solid recos that I would have never considered on my own. The extent of their recommendations went as far as my specific seat assignments. For a 13 hour flight, I welcome this level of expertise. I highly recommend.