>That's why you basically need a third party if you run an ecommerce website, unless you have a team to track down every time a county or city changes their tax

>That's why you basically need a third party if you run an ecommerce website, unless you have a team to track down every time a county or city changes their taxes. Every ecommerce site already has to calculate taxes on checkout, already has a third party for this information (usually the payment processor).