Very sorry for the delay in responding Dan — no excuses!
On sites such as YunoJuno, I openly advertise my day rate, and I don’t have any issues mentioning it when asked. I work from a base rate and then depending on location, working hours, etc I top it up to cover extra costs.
The only reason I don’t have it on my site is because it complicates things, and I’ve found it easier to fully grasp the task at hand and then reveal my day rate. There’s always someone who wants you to work in London, but at my Manchester day rate!
Hope that helps.