How much is this going to cost me?
Questions like these are reflective of the wrong mindset, and should make you probe further to make certain the individual you're speaking to is truly a prospect at all.

YOU: "It's not about spending money, it's about making money."

Then proceed to ask them YOUR next question. Later, after they've reviewed your information and received an overview on your opportunity/product, give the price.
The point is they don't even know what it's all about yet. There's no value to it, until they do. If they persist after your response, end the interview and disqualify them.
Bob