At work, I'm known as "the guy who works out." Over the last couple months, people have been expressing an interest in exercising with me and have been asking me a lot of advice. There is a cheap 24-hour gym on the other side of the parking lot, which is where I go, and a lot of my coworkers have expressed an interest in joining. I'm definitely willing to help them out, even do some initial assessments and write up some workout plans for them. As much as I don't want to do it, since these people are my friends, I feel like I should charge them for my work. I am certified now, after all. Would it be bad to make money off of this when the gym has its own staffed trainers?