Based in the EU means they have to collect VAT for all EU customers. And the VAT amount depends on the volume of sales. If they sell more than a certain amount (€100k) to a specific country they can collect the VAT rate for the buyer country otherwise it is the seller country VAT. And the VAT seems to be 20% in Czech Republic. (see http://en.wikipedia.org/wiki/European_Union_value_added_tax#...)