Foreign Company Performing Work In Thailand

We are designing and engineering a processing plant for a large Thai food company in Thailand. Some of the technical construction work will be done by our Vietnamese construction company. This Vietnamese group will sign a contract direct to the Thai company building the processing plant. After which the Vietnamese group will have to bring in several local Thai subcontractors under them to facilitate certain pieces of work. Tthe Vietnamese group wishes to open a local bank account for this project only, receive all funds into this Thai bank, pay all subcontractors from the account and all tax/VAT issues. Then once all is clear in Thailand close the account and forward remaining profit to Vietnam.

I have a few questions to make sure we are on the right track fro this work:

• What specific tax/VAT issues will have to be cleared for The foreign company?
  
• Will a Thai bank open an account for a project specific purpose to a foreign entity?
  
• The Vietnamese contractor will have to bring technical equipment into Thailand to facilitate the work and then take it back out when all is finished. Would it be best to execute a short-term lease to the Thai food company so there are no issues in removing the equipment when the work is done?
  
• Are there work permit issues here for the foreigners? (All basic and mid-level management labor will be Thai, only tech and high level management will be foreign.,of the 300 workers for this project 4 will be foreign)
  
• Any other curve balls for this scenario in Thailand that we will encounter from a business-structural point of view?
  

Many Thanks,

KHR