How much does a K2 permit cost?

I'm curious, could you tell me what the typical cost is for obtaining a K2 permit? I've heard that it can vary depending on various factors, but I'm interested in getting a general idea of what I might expect to pay. Is the fee a one-time payment, or are there any recurring costs associated with maintaining the permit? Also, are there any discounts or exemptions available for certain individuals or groups? I'd appreciate any information you can provide to help me better understand the financial implications of acquiring a K2 permit.