I have my shop set in Spain and so all products have got a 21% tax (IVA). I have configured taxes in backoffice so that all prices appear with the tax included. The thing is, there is a region of Spain (Canarias) where this tax does not apply and it should be 0% tax, which I have also solved by configuring the right things in backoffice. So now, prices are always shown with the 21% included, but when a person from Canarias starts the checkout process and enters their address, the 21% is removed from the price automatically. So far so good.
My real problem is that if a person from Canarias starts the checkout process, enters their address, but does not finish the payment, then their address gets stored somewhere (I don't know how this part works) and from now on, all prices in the website appear without the 21% tax until the user finishes the checkout process, then all prices are shown with the 21% included again. I wish there was a way to NOT store the users information when he/she quits the checkout process unfinished. Any thoughts?