Estimation Builder has a notifications area in the top bar, so any in-app messages are gathered in one place instead of scattered around the screen.
The notifications bell
Look for the bell icon in the top navigation, on the right. Click it to open the Notifications dropdown. When there's nothing waiting for you, it simply reads "You're all caught up."
Tip: The most important account messages — like a trial ending soon or a payment that didn't go through — also appear as a banner right on your Dashboard and Account pages, so you won't miss them. See Fixing a failed payment.