As a non-European visitor visiting Europe you will pay VAT on most things you buy. The VAT Retail Export Scheme allows you to reclaim a VAT Refund on most goods you intend to export from the European Community. You must export them by the last day of the third month following that in which the goods were purchased.
Should the retailer be part of the Retail Export Scheme they will give you a VAT Refunding Document. This should be presented to Customs along with the goods when you finally leave the EC. Without a Customs Stamp the form will be invalid.
With the form properly validated there are a number of choices you can now undertake. You can post it back to the retailer, return it to a VAT refund company (available if the retailer has decided to outsource this service), or should there be a cash refund office at the departing airport, the refund can made in cash'
Several Travelex bureaux are Cash Refund Offices for a number of refunding agents, Global Refund and Premier being the major ones. Should their forms be presented at these Travelex locations at either Heathrow or Gatwick Airport in the UK then they can be exchanged for cash instantly. There is no extra charge for this service.