The AVS marketplace connection uses the tax identifier to identify the age category of the guest for the local tax. A feature that pre-fills the tax identifier (based on age of the guest) would make the life of hotels that have to use AVS a lot easier.

For example:
if guest is an adult, always set XX in tax identifier field.
if guest has the age of 13-17, always set XY in tax identifier field.

In 99% of the cases we would leave this untouched, but we would need the possibility to change the field (best case via drop down menu), as for example guests with a disability don't have to pay the local tax.

Right now we would have to fill in every tax identifier field for each guest by hand. The fact that the list of arrivals doesnt show the tax identifier makes it even harder, as we have to click through and check every single guestprofile on the day before arrival.