I have a step by step procedure in place. I send email after their call with all our details, I schedule an appointment to take a look at their project.  Send over bid within 48 - 72 hours.  I give them a week and then I follow up.  Most people have other bids they are getting, so I like to give them time.  Once I get the ok, we receive a signed contract and deposit.  We stay in touch giving them updates.