Currently the option to select a currency other than base currency is very limited to few features like projects. The real value of this feature will be when we are allowed to select a currency everywhere throughout Zoho invoice.. I was trying to add a custom column in 'payment received preferences' to note the Paypal fee deducted from my USD payment, but the currency is by default the base currency INR without any option to change it. I experienced similar problem while trying other features also. It doesn't make sense.
Please allow us to freely change the currency for each customer and each feature of zoho invoice.

Thanks
Laksh