Cannot Answer A Simple Question

I phoned this morning to find out how much it would cost for PostNet to send someone to the China Visa Centre in Sandton City to collect my passport. I could not get a straight answer. I needed to know that answer before discussing subsequent logistical arrangements. If the staff member is unable to answer such a basic question, can I even trust PostNet to collect the passport? They might organise my passport and my visa to go missing if they are unable to even answer one simple question that I repeatedly tried to get an answer for. Instead of making a sale by answering a question, the person kept interrupting with what she wanted to say and without telling me what I needed to find out first.