A couple of thoughts:

1. Because you do not have a problem getting instructors. I would make sure that they know that this is a new effort and you will commit to them if they commit to you. The most important way to get additional business is word of mouth. I would still go ahead and do the class even if you have a handful of people and explain to the instructor this is partnership and part of the partnership is to help build class enrollment.

2. Consider a promotion that enroll in one class get the second class for 50% off.

3. Consider alternate (less expensive) venues to keep down rental expenses.

I hope this helps.

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