First, Thank you kindly for all your efforts in supplying supporting documentation and additional explanation of the Thai Tax/VAT Laws.
As requested, I have pulled and reviewed a few invoices received from services provided in both Singapore and Vietnam.
Here are my findings:
Seletar & Changi Airports, Singapore & Tan Son Nhat Int'l, Saiigon, Vietnam -
2nd tier supplies (caterers, airport, transportation companies, government authorities) charge 7% VAT/GST >> 1st tier (Handler/Supervisor) no additional VAT/GST added on their invoices at all.
Example:
Transportation Company charges $100 one way +$7 (7% VAT) = $107. Handler pays that bill directly to Transportation company and re-bill Rockwell Collins $107 + disbursement. No additional VAT/GST.
It is for the above mentioned example that we ever questioned the additional ASA 7% Tax.
Trust, I am working diligently on my end to find resolution soonest.
Should you have any questions in the meantime, please do not hesitate to contact me directly.