How much do you charge for a bank certificate at all?

Recently, I plan to apply for US VISA as visitor. So I've been preparing my documentations, such as bank certificate, monthly statement..., something is funny, maybe it's a tip for saving money too. When I go to Chinatown Branch of BMO bank, I was told that they would charge me 10$ for one bank certificate, but I don't need to pay this fee at the other bank around Mcgill metro.