Provide technical support to the service team, and hold weekly/monthly meetings to discuss new products and bulletins. Solve customer problems via phone or site visits. Ensure customer satisfaction by following up on complaints. Act as a communication bridge between After-Sales and other departments. Review and approve contractor invoices (installation, ductwork, transportation). Conduct survey visits for VIP/Mega Projects. Participate in negotiating tender contract terms. Forecast materials/tools needed for the upcoming year.