I’m a trainer who prefers the outdoors and I rarely train clients at gyms. I’m not sure how confident you feel about this, but my suggestion to you is to take them outdoors or at the very least train them at their apartments/homes. I see you reside in Southern California where the weather is almost perfect, so why not take advantage of it? I know San Diego has some great locations for training and I personally believe the best workouts are done when using the surrounding environment to our benefit. Plus, you will avoid all kinds of legal and financial issues you will need to resolve if you are going to use a gym, apartment complex facility or any other type of fitness center. This is just another option for you to consider.