After meeting with a prospective client, please fill this out to the best of your ability:

Were they laid-back or upbeat, quiet or outspoken, professional or casual
Do they communicate their thoughts well (in person and email)? Have you had to ask for clarification on anything?
Email, phone, or in person?
Are they quick to get back to you or does it take a day or two?
Do you anticipate they'll want to have a say in most decisions we make?