Hi Delmar. You sound like a person wanting to ‘do the right thing.’ In this instance, the ‘right thing’ is not to try to train under the table. While some might get away with it, if something should happen, you could find yourself in a world if legal trouble, not to mention the damage to your reputation as a fitness professional. I always say, do things the right way, which in this instance would be to ask the management of the gym if training there would be possible. You can make it a win-win by doing a fee-share with the gym. That way, those clients who want to train, get to train with you, you get a fee, the gym keeps satisfied clients and makes a small revenue to boot. Everyone is happy!
I hope that this helps.