Autopage
Recover postal expense from client at R9.50/lette

I want to know why I am billed for posting my monthly invoice to me. Why do they charge R9.50, while the standard rate at the post office is R1.67? Am I as client liable for their postal expenses? I am sure that I am not the only client effected by this. Several phone calls in this regard over a period of 6 months, and no anwer yet.