In this tab you can find everything related to currency in QEstate theme. It is possible to add as many currencies, as you need. Add for each currency symbol and change some visual options such as decimal separator, thousand separator, etc..
Use "Add Entry" button to add new currency. If in currency list you can't find currency you need or want to add something special (f.e. Bitcoin, Ethereum or any other cryptocurrency), you can use "Custom currency" option.