What are the preparations needed for a sales call?

From my experience, I believe that it is always necessary to maintain a wide range of alternatives when performing any important activity.

With the passage of time and implemented the following alternatives:

1- Do a quick background check through LI or CB.

2- Have a Google document prepared with all the basic company information and objections/questions if available.  

3- Take notes during the meeting.

4- Send them a follow up email and have them sign off.

5- If it is an exit meeting and there is no information, you have to probe and improvise.