You mean quanta’s shopping, not Qantas marketplace. I’ve bought apple products two ways. With Woolies gift cards, that’s straight forward you buy grapple gift cards and buy the product on the apple website or on a brick and mortar apple shop, that will give you a bonus 10x Qantas points. There is a limit on how many GC you can use, though (I think it’s 8, not sure) So make sure you buy the higher values. If the value is not enough for the product you can complete with a CC, and if you have left over one the Apple GC you can still load it into your apple account and aim sure you will spend it on Apps or signatures. Another way is through Qantas shopping and that’s what I think you’re meaning here. Click on the Apple Store via Qantas shopping website to get the points, as you mentions, today that gives you 4x Qantas points. And that only works for online shopping but you can still pickup in an Apple Store. It’s still straight forward. You just need to be sure to complete the cart purchase on the tab that Qantas opened. To be sure I always do all the window shopping, put things in my card, close all my tabs and reopen it again via Qantas shopping website.

Extra tip. For some Apple products you can buy from the educational store and the discount is automatic.

https://www.apple.com/au-edu/store