I have never talked to sales. How do they find this out smoothly, without insulting the person being talked to for not having any actual authority?

They ask something along the lines of “What does the process look like on your end” to figure out who makes the technical, legal, executive and financial decisions.

Because often in larger companies you got approval, then you go testing and the users approve as well, and suddenly either legal, finance or your manager pulls back. So they want these people in the loop and signing off as early or quickly as possible, to avoid wasting their time.

That’s also why the sales people usually state how important it is to have clear small and measurable goals. It’s not only for you to figure out if the solution works, but to have you set up small and clear internal criteria to sign off on as quickly as possible.

They pretty much just ask. "If there's an opportunity here, who makes the decision?" And they'll want to know if there's a technical decision maker and a financial one.