IDEA: Ask your customers how much they spend with your competitors, just to start.

Have your sales personnel ask current customers how much they spend on your types of products with other firms. Some buyers will be glad to tell you and some will refrain. It is good if you can get a ball park number but it is more important to know that this buyer can immediately tell you how much better the competition is and what they do that you do not.  You need this feedback and information about how you are losing in the market.  If they cannot tell you a dollar amount or maybe not allowed to discuss it, tell them is fine but you would like to know what you like the best about the competition.  This is a buyer who has seen you and your competition and can differentiate who is easier and more professional to deal with.  Take the opportunity to ask. You will learn some things and that is a good idea.