Certainly! CoinMaster (and its sister companies) were one of the first entities in Greece to accept Bitcoin as a means of payment. We also accept other cryptocurrencies like Litecoin, Ethereum, DASH, PIVX and Bitcoin Cash.
To facilitate the calculation of the conversion rate, CoinMaster has developed a specialized tool: The Euro2Crypto tool. Using this tool, you can input the invoice amount (expressed in EUR) and select the cryptocurrency to convert to. The price is dynamically calculated as the average of many different exchanges. you can even make a print out of the calculation, for future reference.
The invoice you will receive will display the price in EUR, with a mention of the cryptocurrency used and the exchange rate.