Commissions

I’m working on a spreadsheet and I’d like to know the various commission structures that you all have (or have had in the past). Can everyone reading this give me a brief explanation in the comments? I will start with what I get from Interactive Brokers. If someone else has already commented with the same structure you have or have had, please don’t repeat it.

I am not looking for dollar amounts (although it is fine if you include them). I mainly need the structure; i.e., if there is a ticket charge, if per option price goes down with higher quantity, if there are set prices on all options or if index/ETF/ etc have different prices, etc.

Thanks!