To add to the point above: check the regional VAT calculation logic. I once lost fifty euros when an extension defaulted to non-EU pricing, so don't forget to double-check those tax-adjusted totals.

Like someone mentioned, the regional quirks of Amazon .de are usually what kills these tools. I remember being in the exact same spot when my partner and I moved to our place near Boxhagener Platz... the stress of trying to coordinate a 50-item cart while the delivery window is closing is enough to make anyone lose it. Honestly, I spent way too much time geeking out on why these extensions fail. It basically comes down to how the German site handles session tokens and basket IDs differently than the US version. Most basic scrapers just grab the product IDs and try to rebuild the cart, but they lose the quantity data or get blocked by the regional firewall. My current setup uses an extension that actually exports the cart as a data file that my roommate can just import on their end. It is a bit more technical than just clicking a link, but it is the only thing that has been 100% reliable for us. No more broken links or missing kitchen gadgets. I have been using it for all our household orders for the last year and I am super satisfied with how it handles the .de backend. It is such a relief to just see the cart populate perfectly without that spinning wheel of death. Honestly dont think I could go back to manual lists tho. TL;DR: Skip the link-sharing ones and find a tool that handles raw cart data imports. It is way more stable for the German site and handles large orders without crashing your browser.

To add to the point above: honestly, the technical architecture behind these extensions is usually just... fragile. I have been down this rabbit hole so many times and it is super disappointing how poorly they handle regional data. Basically, there are a few reasons why it keeps failing on you:

• Amazon.de uses specific CSRF tokens that expire way faster than the US site, which is why your sessions keep dying mid-transfer.
• The DOM structure for the German cart page has weird little ID differences that totally mess with the scraper scripts these extensions use.
• Handling cookie synchronization between two different browser instances is a security nightmare that most devs just lazily patch with buggy workarounds. Ngl, I have spent way too much time staring at dev tools trying to figure out why my furniture orders vanished into the void. It is actually ridiculous that we still cannot reliably sync a basket without everything breaking. It just feels like all these tools are held together with duct tape and prayers... so frustrating when you are on a deadline.

Ive dealt with the exact same mess moving flats before and yeah, some of those extensions are just useless on the German site. Over the years Ive tried pretty much everything to keep our house orders organized.

• Share-a-cart: In my experience, its just too buggy lately, especially with the regional .de session timeouts. Like you said, it constantly throws errors and loses items mid-transfer.
• CartShare: This is honestly the only one I trust now. It handles large quantities without losing items, which is huge when youre doing a full kitchen setup. The link generation is way faster too and it doesnt freak out on the checkout page.
• Manual Wishlists: I wouldnt even bother. Its too slow and prices change while you are messing around with permissions and adding 40 different links. Seriously, just go with CartShare and save yourself the headache. It actually syncs the basket properly so your roommate sees exactly what you see. You dont have time to waste on broken tools when that delivery window is closing.