There are seven icons you'll see on the view/add page:
Green Check Mark - Means this job has been completed.
Dollar Sign - The invoice for this job has already been paid.
Red Text - This customer has an outstanding balance.
Crossed-out Circle - The agreement for this customer hasn't been signed yet.
Blue Credit Card - This customer has card on file.
Green Credit Card - This customer has auto-pay enabled.
Red Padlock - means the job is hard scheduled.