"Do you have a tip to share to make this process more efficient?

A CPA nearby me fired 25 clients last November who were constant laggards and didn't get going until October."

This is the method we use, as well. I'm only working today because one of my guys got a K-1 from an entity he doesn't control yesterday morning!

Bits and pieces doesn't bother me, but it's a really inefficient (by which I mean expensive) method. Most of my clients give me everything (or everything but the brokerage statements I have online access to) at once.