I shifted to using Christmas Wishlist Creator because it manages the inventory data in real time. It solves the duplicate problem by locking items once they are claimed. For the in-laws, the interface is extremely lightweight and doesnt require an account to view, which is key. It works well for syncing across different households without any manual status updates. Honestly, it is the most logical choice.

^ This. Also, in my experience over the years, the real killer is when relatives forget to check the list again right before checking out. I tried plenty of apps but my current setup uses one that sends push alerts whenever someone claims an item. It handles the backend sync instantly, which saved me from huge duplicate headaches last year... TL;DR: Pick a platform with real-time notifications so the tech-challenged family members stay updated automatically.