Bringing every module together into simple, concrete math you should calculate for your own product before scaling:

Break-even units = Fixed monthly costs ÷ Profit per unit

Example:
Fixed costs (store subscription, apps, email tool): $50/month
Profit per unit (after product cost, shipping, payment fees): $8
Break-even = 50 ÷ 8 = 7 units/month just to cover fixed costs

Everything beyond that 7th unit each month is real profit — and per Module 10, that’s what funds your next stage (ad testing, then a custom store from Module 5, then hiring help below), not your original starting capital.