MUA self employed rates?

[chanails]

Hi all , Hope you having a great day , I'm expanding my salon to have a make up lounge , I have staff currently undergoing more training who are employed. But also I have a lady who is joining the team , she's self employed Mua artist with a big client following , I'm wanting to make her wage fair for both , anybody in this current situation ?? Make up , furniture everything provided by my salon. I'm wanting to know what the best percentage share . Thanks for reading xxx