Found that out the hard way on a basement job.

Honestly that's a great point from @the_morgan about using a sealed tote. It's the same basic idea as the PVC level, just applied to the whole kit. You see this everywhere once you look for it. People are always finding clever ways to make a simple object solve a complicated problem, especially when the job site itself is working against you. It's not about fancy gear, it's about using whatever is already there in a smarter way. That kind of thinking saves more time and money than any expensive tool.

Totally feel you on the "thought it was good enough" thing. Had a lady last month get down on the floor to look across a seam at eye level, said she could feel a slight ridge. I was sure it was flat but she was right, had to go back and work it way more.

That timer idea is genius... we should try it for our whole meeting.

Hear you, but I see the meters as learning that language faster. Lets you focus on the feel once you know the basics.