In OneOfficeERP, you can create transactions in the foriegn currency as well. When creating transaction in the foreign currency, system updates current exchanage rate with respect to customer/supplier's currency and base currency on your Company. Since Exchange Rate is always fluctuating, one might receive payment from the client on exchange rate different from one mentioned in the Sales/Purchase Invoice. Following is the instruction on how to manage different amount, availed in payment entry, due to exchange rate change.
To manage currency difference, create Account Exchange Gain/Loss. This account is generally created on the Expense side of P&L statement. However, you can place it under another group as per your accounting requirement.