This is both a comment and a question.

I like to define an Adagio tax group as follows: A tax group is (1) a group that attracts a unique set of taxing authorities and (2) can make tax rate changes independently of other the other tax groups.

In Canada, I set up 13 Tax Groups, one each for the 10 provinces and the 3 territories. Even though Ontario and BC, for example, both attract the same taxing authority, HST, they can nonetheless change their HST rates independently of each other, so they fall into their own Tax Groups in my scheme of things. This makes changing tax rates very easy.

Each Tax Group is assigned its appropriate tax authorities, such as GST, PST, HST, etc.

In most, but not all cases, there only need to be 2 tax statuses, Taxable and Non Taxable for both items and customers. I can see where another status, “Partly Taxable” might be appropriate in special cases. When the item and customer tax statuses are not the same, the lower will always prevail on invoices, as it should.

Whenever I have made these changes for clients, I export customers, ship to addresses and items, make the appropriate changes in Excel and import. Open orders might take some Gridview r/w work to align them with the new system.

In trying to keep things simple, whenever possible I prefer to have a single universal invoice that will work with all tax groups. Here is where I need help. Suppose there is an invoice with only one sales tax being charged. My universal invoice uses the following codes for sales taxes
V11 F01
V12 F03
V13 F04
If the tax represented by V11 is the only sales tax being charged on an invoice, printing of V12 and V13 is suppressed, but F03 and F04 show as zeros, which is a bit confusing. Are there better spec codes that I should be using?