If the group has already been shortlisted by using "quick" filters (qualifications, geography, average deal size, vertical), take the time to get to know the few that are left. Choosing the wrong partner costs both time and money, and it is likely that the few will differ in some other aspects, such as fee structure, culture, confidence or sheer experience. Understand how many other businesses is your broker representing to understand if your broker has the right qualifications or experience, how much time can be devoted to your busines, and how they plan to ensure the deal will be seen by the right buyers before deciding who to trust.