How do I approach business development/sales within a B2B startup company with a product still in its prototype stage?

Knowing clients' needs is a key to success. Knowledge of their products and competition is necessary as well.

. You need to know well about your product 2. Understand your potential clients 3. Know their needs 4. How can your product be of great service to your clients? 5. Would you survive if payment for your service is being delayed? 6. How fast can you respond to your product's glitch? 7. Do you have the required expertise to take care of your product's wear and tear?