You can see the price of a course when viewing it from the course catalog. If the course has a cost, it will be listed to the left of the course length.
You can also check the Detail tab of a course. If there is a cost, it will be noted under the title for the course.
Course costs are typically due at the time of enrollment.
NOTE: Continuing Education courses for electrical license renewals through BlueVolt University are the exception. Most of those courses require payment only after you have completed the course.