Regarding speaker fees, I once learned a good rule of thumb from @jessicahische: ask for 2 x the ticket price of a conference.
I think she even used 3 x in her example, and I have used 1 x in the past. But it nicely makes a point that you shouldn’t speak for free at a for-profit event. And you totally can at a free one if your circumstances allow it.

Also, don’t speak at events where you have to pay for your own ticket. Unless it’s a really nice community event you love.