anthonys - thanks for your good suggestions on improving Briantree's signup process. We rolled out a new version of our signup form today, and we are now using the BSB number to determine the type of bank account. We also eliminated a few other fields from the form and are working to simplify it further, by removing the ACN field (which it turns out is embedded in the ABN/ARBN number headslap) and a few others.
I looked into your suggestion about using the ABN number to look up information about a merchant and found http://abr.business.gov.au/. It looks like that will provide the merchant's name along with the city, state, and postcode of their location. Are you aware of any other services that would provide more information?
I am fairly certain nab will be doing a similar search so maybe you can work with them on that or have them reimburse you for Braintree performing the initial search.
Re. ABN/ACN there are certain (very rare) situations where the ABN and ACN differ apart from the additional 2 numbers at the start of the ABN.
I looked into your suggestion about using the ABN number to look up information about a merchant and found http://abr.business.gov.au/. It looks like that will provide the merchant's name along with the city, state, and postcode of their location. Are you aware of any other services that would provide more information?