Another thing to think of, in addition to the percentage, is what other perks you are getting. Several things can affect whether the percentage is “right” for you.
1) Do you have to bring in your own clientele, or do you have access to theirs?
2) Who is doing the advertising – you, them, or both? If it’s print advertising, who is paying for it?
3) What is their social media presence and are you featured in it?
4) How many members does the facility have and how busy are the existing trainers?
5) Do you have specialized training that the facility would want that makes you worth more?
6) What are the training fees? Do the math. A high percentage of a low hourly training fee might be worth less than a lower percentage of an expensive hourly rate.
7) How close the facility is from your existing client base (will people move to be with you)?