Best travel voucher/gift card to buy for my parents to fly to visit me?

[HankWilliams]

Hi all, Random, but I was going to buy my folks a plane ticket to come visit me.

Was wondering if there was a Mustachian way to give them a gift card or voucher for $400. Maybe something that could be 5 or 10% off or have some benefits. Thanks a lot.

[honeybbq]

I'd just send them a homemade card, maybe printed with an airplane or something, and make it look like a pretend gift certificate.
Then tell them you'll purchase the plane ticket when they give you the flights they want.

[JoJo]

If you know what airline they will take, look at getting that airlines' card and getting points and/or cash back on a purchase of tickets.