How much does ICO cost?

I'm curious about the financial aspects of Initial Coin Offerings (ICOs). Could you elaborate on the typical cost involved in launching an ICO? I understand it's a complex process, but I'm seeking a general overview of the expenses one might encounter. Are there upfront costs like registration fees or development expenses? Are there ongoing costs such as marketing and legal fees? How does the cost scale with the size and scope of the ICO? I'm also interested in knowing if there are any hidden costs or unexpected expenses that often catch projects off guard. A breakdown of these costs would be immensely helpful in planning an ICO.