VAT is easy for consumers of course, especially given that you have the bright idea of making the final display price include all fees and taxes and no tips, unlike some people who seem to drink mercury on a regular basis. Some places to my knowledge have a system where the amount due is simply withheld from the paycheque, and you get a message by mail or email or fax or carrier pigeon or the Persian couriers attested to by Herodotus or something which shows the calculation math to prove to you that the amount is right and how you can complain if you think it's incorrect.