If I am correct, the basic approach to Taxes and Charges has not changed/updated, I believe since the basic design of ERPNEXT (or al least not since the 4 years i am using the system.)
There are some shortcomings, i believe:
- Taxes /charges cannot be calculated on an quantity, which may be the case for petrol or water billing, or charges for transport
- Also users may want to calculate a tax/charge but does not want to include that in the total amount of the invoice (eg a reversed tax charge, or delivery cost that are booked but for customer the delivery is free,…)
In Brazil (@max_morais_dmm) things seems to be very complex
May be you can add your ideas here how the present functionality could be extended, in such a manner that the end-user may calculate taxes/charges without going into custom scripting