Know the competition

With business rivals, honesty is the best policy.

Being direct, honest, and upfront will help keep you from being blindsided later, and in many cases, it will allow you to truly understand the viability of the opportunity. When someone asks you about a feature your competitor offers, the best response is simple, "Yes (or no), we can(not) do that. I am curious, how important is that feature for you to make this decision?"