Litmus test?

Has anyone ever found a successful way to gauge how much work a shop actually has to offer? Might have to go back to wrenching and it’s always been the same issue in the past. “We have more work than we can do and we’re turning work away” “guys are turning 90-100 hour weeks there’s plenty of work”

starts

Techs barely turning 40

I’d love to hear if anyone has a good way to judge a place before/during the interview process aside from scoping the parkinglot.