When trying to determine what the tax default is, Spectrum considers the following:
The Utilize tax classification setting and the Tax class default setting (is it set to job or vendor?) in the Job Cost Installation screen.
The vendor tax setup (is there a tax code present?).
The job tax setup (is there a tax class code present in?).
The tax classification setup (what is the A/P tax code and are there any cost type or phase overrides in?).
Spectrum allows you to set up all tax information in either the vendor or the job, but you can also use both sources and even overrides. Furthermore, if the Utilize tax classification checkbox is selected in the Job Cost Installation screen, this allows you to set the exemption flags in Tax Classification File Maintenance that will be used when processing A/P invoices.