I have a google form that I send to clients as soon as they pay their "equipment payment" (which is typically 4-6 weeks before final) that has the names of every current service their system will support, and asks for their username and password. I resend it every Monday until it is filled out and returned to me. I have had to threaten to hold up scheduling the final system delivery over this.

I will not have my guys hamstrung on a job-site for a half day trying to chase down passwords...even if I can bill for it, my calendar can't accommodate it.