In The Marketing Plan Handbook, author Robert W. Bly explains how you can develop big-picture marketing plans for pennies on the dollar with his 12-step marketing plan. In this edited excerpt, Bly describes the biggest selling mistake you can make and offers a formula for how to avoid it.

How much do you know about your ideal client? And why does this matter? It matters because meeting your clients’ needs bet­ter than your competitors do will always be your first job as a busi­ness -- if you intend to own a successful business.

The closer you are to your market, and the more you understand them, the easier it is to quickly build a stronger relationship with them. Prospects are people who have identified themselves as potential customers through some action (for instance, subscribing to your e-newsletter or requesting your catalog), but who haven't actually made a purchase. You can land these prospects by marketing to audiences, through various media and mailing lists, who fit the description of your target market but who don’t know you yet. We can call the people in this vast prospecting universe “suspects.”

For example, if you're a chiropractor who specializes in relieving back pain, everyone in your town may be a potential patient but you don’t know whom to target, since you don’t know who has back pain and who doesn't. These are your suspects. Now, you run an ad in the local weekly newspaper advertising a free seminar on relieving back pain next Tuesday evening. That Tuesday, 32 people show up. Unless you're serving a free lobster dinner, only people who have back pain or know someone who has it will come. Therefore, your marketing has successfully completed the first step in the sales process: converting suspects to prospects.

On the other hand, a customer is someone who buys the product now from you. Some business writers separate these buyers into two groups. Users are people who buy your product but aren't passionate about it; they're often impulse buyers. Customers are those who buy the product after a deliberate consideration of its benefits; they make what are called “considered purchases,” meaning they've considered the buying decision carefully. Beyond "customers" are buyers so satisfied with your product or service that they proactively recommend it to others; these are called “advocates.”

But getting from the prospect to customer to buyer stages isn't easy -- and that's where the number-one selling mistake that causes entrepreneurs, executives, salespeople, and professionals to spin their wheels, waste their time chasing after people who don’t want to buy, and experience enormous frustration when following up leads rears its ugly head.

That mistake is the failure to determine whether the person or “suspect” making the inquiry is a genuine, qualified prospect or just someone who likes collecting brochures and wasting salespeople’s time. But how can you quickly, easily, and accurately determine whether a lead is a qualified prospect? By using my “MAD FU” formula.

The MAD FU formula has nothing to do with anger, or any other emotion, or the “F” word. Rather, MAD FU stands for the five qualities that differentiate a qualified prospect from a time-waster or tire-kicker: Money, Authority, Desire, Fit, and Urgency.

MAD FU says that to qualify a lead, you have to ask them questions. These questions determine whether they have the money to afford what you're selling, the authority to buy it, and a strong desire to own it. In addition, are they a good fit for your business, and do they have a sense of urgency?

Let’s look at how to quickly assess all five factors. First, money: Can the prospect afford what you're selling? The easiest way to determine this is to ask, “Do you have a budget for this?” Without a budget, how can they possibly buy your product or service? If they say they have a budget, ask, “Would you mind sharing with me what your budget is?” Their answer tells you whether they can afford you or not.

Second, authority: Can the person you're talking to write a check or purchase order? You can determine this by asking, “Who else in your organization is responsible for making this purchase decision?”

The third factor is desire. How intense is their desire to own your product or get your service? How important is it for them to take care of the problem your product would solve for them (e.g., reduce energy costs, control inventory, etc.)? You can gauge their desire through the content of your conversation with them as well as tone and body language. The best prospects have a burning desire to own your product or have you solve their problem.

The fourth factor for qualifying prospects is fit. Is this person a good fit for your business? Is there good personal chemistry between you and them? Does your product or service best meet their needs, or would they be better off using another vendor?

The fifth and final factor is urgency: What's the prospect’s time frame for taking possession of this product or having this service performed? The more the prospect is in a hurry, the easier the deal will be to close. But if the prospect has no sense of urgency, you may spin your wheels for months -- even years -- chasing after them.

The lesson? When your marketing generates a phone call or email inquiry from a potential customer, don’t get too excited. Instead, immediately qualify the lead with MAD FU. Does the person have the money, authority, and desire to buy? Are they a good fit? Is their need immediate? The more “yes” answers you get to the MAD FU questions, the better your chances of making the sale.