Invoicing: note about reverse charge

[clstaudt]

If you ask VAT, for billing purposes you might also want to know if Reverse Charge applie

This was with regard to VAT percentage. A freelancer in an EU country that bills a company in a different EU country would sent invoice without VAT but would then need to add that sentence about reverse charge on the invoice. It is probably not an important use case for a first version of the tool, though, just something that came to mind