How does Vat work?
Vat is a tax on goods. If the person you are being from is Vat registered, he will add 20% to the final price.
So if something is £100, 20% needs to be added.
However, as a customer you pay the final price and sometimes do not see the VAT breakdown.
It is possible to work it out.
Taking the same example, the price you paid was £120.
You use a fraction of 1/6.
So 1/6 x £120= £100
Thus £120-100= Vat paid.
When you fill in your Vat return, you claim £20 back.