Your kid's business just made 15 sales. They're excited. They counted the money, calculated their profit, and feel like a real entrepreneur. But here's the question most young business owners never think to ask: How much did it cost to GET those 15 customers? If they spent $5 on flyers and got 15 customers, that's about 33 cents per customer. Not bad. But if they spent $30 on signs, posters, and printed materials? That's $2 per customer. Suddenly those sales don't look quite