Your customers are smarter than you think they are. They realize that you can't be all things to all people. When you are honest about what you can't do the trust they have in you goes up.
Here is an example.
A test was conducted on the advertising of five products. They ran two ads - one that said they had superiority in all five products and another ad that claimed superiority in three of the five. Which one do you think did better? The advertisement that exposed their weakness did much better.
Why? Customers have become numb to selling pitches and marketing that promises miracle cures. When you make a statement like "this may not be the product for you" your credibility has increased. The customer has more trust in you.
I know. I know. This sounds like the old joke about the sales person who says "you don't want to buy anything today, do you?" This is different. This is admitting that you can't deliver the moon. This is being honest. This is building trust. And people will only buy from people they trust!
When you honestly state a weakness, you are actually helping your customer make a good decision. They will believe you when you tell them what you CAN do.
The advertisement used by Chevy a while ago is a good example. Chevy compares itself with Honda and says they are superior in five models except one. Chevy does not make lawn mowers and Honda does. In their example they use it with humor, however, I don't think they realize how powerful the technique could be if they used it with a tone of seriousness. The fact that Chevy could be big enough to admit that they are highly superior in certain models while admitting that they are not the leader in one or two categories (with justifiable reasons) their believability would be higher.
When there is even a small doubt in your mind about whether the product is right for them, let your customer know. Let the customer know you will be personally checking to make sure that your product does the job and the customer is happy with the purchase.
Remember, you can't sell anybody anything. The harder you try the more the resistance goes up. What you CAN do is help them make a good decision. You want your customer for the long haul, not just the immediate sale that will come back to bite you. Especially if you over promise and under deliver.
As a professional speaker, I have turned down plenty of opportunities because I didn't feel I was the right fit. Of course I had to learn this the hard way. I teach sales negotiating. How to make more money by giving more value. I once accepted a speaking engagement for a government agency that really didn't understand the profit concept. Needless to say, I didn't connect with the audience. I now know better. It is not worth the paycheck when you leave knowing that you blew it.
So when something comes along that is not a good fit, I let them know and they have much more faith and trust in me. Somehow turning it down always seems to come back in good way.
I can't teach the government how to make better deals, but I can sure teach YOU how to increase your sales and profits in these challenging times.