Honestly i've been through this struggle so many times with my roommates. It is a bummer amazon makes it so hard to share but i guess its a privacy thing with how web sessions work. I've been using Share-a-Cart for a couple years now and honestly i am super satisfied with it. It basically takes a snapshot of your cart and creates a unique code you can text her. No account info or passwords actually get shared which is why i have no complaints about the security side of things. She just pops the code in on her side and it fills her cart exactly like yours. Another technical way is to use the Manage List feature and invite her as a collaborator but that is way more clicking around since you have to move every item manually. Honestly just sharing the cart directly is way faster for getting that fire pit sorted before the 4th. It works well and saves a ton of stress.

Late to the party here but honestly, its so disappointing that Amazon still hasnt figured out a native way to do this. Youd think a multi-billion dollar tech giant would have a collaborative cart feature by now, but unfortunately, we are stuck with workarounds that arent as good as expected. Technical limitations with session cookies and secure tokens usually prevent a simple link from working. Since you are worried about the 550 total and that premium fire pit, here is how I usually handle it to avoid cost drama:

• Set up a fresh Idea List instead of a standard Wish List. It actually lets you add comments to specific items, so you can explain why the 250 dollar fire pit is better than the 150 dollar one. Maybe mention the better gauge steel or heat radius.
• If you use the extension, just be careful with browser permissions. Some of those tools read data on every site you visit, which is a bit of a security red flag imo.
• Double check the shipping dates for each of those 45 items individually. Since you are in Austin and need it by next week, some of those string lights might be shipping from third parties and wont arrive in time for the 4th. Moving items one by one is a total slog, but the list method is the only native way she can see the exact specs and reviews without needing your password. There is a good breakdown on Smartphone Board about using extensions vs manual sharing for Amazon.

I had this same issue with a huge camping order last summer. Amazon still hasnt added a direct share button, which is kinda annoying tbh.

• Share-A-Cart extension is a decent option. It creates a code she can paste to see that fire pit and everything else.
• Moving items to a Shopping List works too, even if its a bit slower... Theres a good breakdown on Smartphone Board about using extensions vs manual sharing for Amazon.