I hate math but Tony you are a teacher....help me here... $400,000 with 10% down and the balance on a 5.5% SBA loan would be what kind of monthly mortgage? Then figure in the rest of your overhead (rent + improvements, insurance, manager cost, utilities, supplies, etc.) and variable costs (party supplies, contract puppeteers, actors, etc.) What kind of a monthly total would that be just estimating?
Then figure out how many shows you would need to host to pay for that every month. Not just the gross income, but the net income (after costs). At what level would it be profitable? Perhaps 10 shows are needed to break even (equal to your costs) after that the rest you can host contribute to profit.... could you do 25 shows a month?
Would be fun to play with the numbers since you know the cost of the building. Here something like that would probably be 1-2 million.