How much should you pay for a managed fund?

Good afternoon, I'm curious about the topic of managed funds and their associated costs. Can you please elaborate on what factors should one consider when determining how much to pay for a managed fund? Are there any industry standards or benchmarks that can serve as a guide? Additionally, how do the fees charged by managed funds typically compare to other investment options, such as self-managed portfolios or index funds? Lastly, are there any potential hidden costs or fees that investors should be aware of when investing in a managed fund? Thank you for your insights.