@seahawk aka Wynand
1. For Items:- What happens if you have different rates of VAT eg 8% 10% & 19% then you would have a different item tax type for each rate, so on the day of the C/O create the new different taxes, 9%, 11% & 20% and assign the relevant item tax type to its new tax rate, not tried this, but no individual item setting would be touched.
To clarify:-
2. For Suppliers & Customers:- each customer is assigned with a tax group, lets say this is called VAT with a rate of 14%, then create a new tax for 15%, assign this to the tax group VAT, so now all customers and suppliers will be charged VAT @ 15%. Should you need to create a credit note, create a new tax group call 'VAT@14%' with an assigned tax of 14% change the relevant supplier/customer to this tax group, create the credit note, change supp./cust. tax group back.
I like your idea of taxes by date.
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