I count you as a card, 3,000 wage earners, 2,000 white-collar workers and 5,000 ~1w. It is obvious how much money you can collect from 100 members. If money can't meet the rent, industrial and commercial water and electricity can't be done anyway.

Calculate your hard cost, combined with the consumption power around you, you can get the least number of members. On this basis, increase by at least 50%, and then establish a business basis (such as the salary of cleaners and coaches and depreciation of equipment). However, selling cards can never make a lot of money, and the income from selling classes by coaches is the mainstream of making money.