As a CE instructor, how much do you pay in fees to your space rental/admin

My school wants me to bring in CE providers.  I am unsure what to charge.  I want it to be reasonable for the CE instructor, esp. since we ask for our students to receive a discount on the classes, but I also have to make money for the school.  I will be providing administrative support for the person, doing the marketing, handling money, etc...
Thanks in advance!
Kelly Grounds
Georgia Career Institute, Mufreesboro