I guess it also depends what market you are in. In NJ, just outside of NYC, I hire MUAs who also do hair for my shoots at a rate of $100 to $120 for the shoot consisting of 3 looks / 4 hours. I have always been happy with the results. I shop around, and find the best portfolio for the money, not just pay someone what they are asking.
There are MUAs that do weddings in my area that charge $700 to do the makeup for a bride. People charge what they can get, and if you are THAT GOOD, you get what you ask for. Oh, and my wife hired one of those $700 / 1 hour of work on makeup only MUAs when we got married, and yes, I paid for it w/o complaining
. If you knew my wife, you would understand why.
Do your research, and compare people's rates.
Just my 2 cents, but what the hell do I know anyway.