Hi there. Thanks for taking the time to connect with us here. I'll be happy to add more info about using the Multi-currency feature in QuickBooks. Once Multi-currency has been turned on, you won't have the ability to change the currency. If you wish to operate your account using a different base currency, I recommend looking into setting up new account using the link provided above by Fiat Lux - ASIA. Otherwise, let me know if you have questions, I'm here to assist.