General rule: services exempt unless enumerated; load testing not enumerated. Only HI/NM/SD/WV tax services by default. CPA-confirm per state.
Invoices shipped to AZ
Invoice
HWI #
Customer
Date
Total
Class
Taxability
Source
24412
HWI-25-333
Insultech
2026-01-28
$471
rental
TAXABLE (rental)
packing-list · distinct
Determined liability = taxable rental (+ resale, + service where the state taxes services) × rate.
Offshore rows are treated as exempt (cert-controlled). Floor = state base; combined adds avg local.
Figures are pre-exemption-certificate and pre-credit — CPA/SALT validate before filing.