@RomanovM Thanks for adding to the discussion. The question still remains - in version 4.2 is the tax service called each time a product page loads, even if tax is not displayed on the product page? Has the call count to Avalara been tested by your team? If the service IS called each time the product page loads Avalara is not an option based on our site receiving 70k+ visitors each month. That means we would be 250,000+ calls to Avalara.
Our plugin is not called for each page load. Please see the implementation here. As you can see we cache results becased on the address used for tax calculation. So it's invoked only once for each unique address