Great question — answering as the UphillTech team:
I assume that if you need this implementation is because you have a VAT-excluded price in a Shopify product, right? I've already done that implementation on other stores, but I always write that liquid in every section (collection item template, product, cart) because there are a lot of different classes and other things. Another solution, a bit tricky, is to create a snippet where you calculate the VAT price (you have to send the price to the snippet every time). Then, render it where you need it. For me, it's easier, also easier to manage to write these 5 lines of code where I need them.
Full answer by Aleffandro321: https://stackoverflow.stackexchange.com/a/79600433 (CC BY-SA 4.0).
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