|When you encouraged your friend to go into sales, you did not provide him with a wild card that lets him sell whatever he wants to you. At the same time, although you are satisfied with your current supplier, it is always worthwhile to see what else is being offered in the marketplace, whether from a friend or not. It is possible that your friend's company has something better than your current supplier.|
Let your friend make his presentation to you. If you still find that your current supplier better meets your company's needs, you can tell him that. You are not rejecting him as a person, but only rejecting his products at this time.
One additional step that can help in this situation is to let him know what it would take to get you more interested in his company's products, such as in terms of function, features, or pricing. Secondly, you can provide him with names of people in other companies whose needs may be a better match for what he is selling. To a real salesperson, good referrals are like gold.
His reaction will tell you a great deal about his salesmanship and friendship.