Sometime ago, I posted this question on the economics.stack and now I don't know how to proceed. Should I accept an answer, or should I let it be free?
Generally, if there's an answer that was most helpful and "settled the debate" for you, you should accept that.
I like that specific question a lot, and I'm a bit worried that accepting an answer might deter people from posting more answers. In that respect, I'd suggest you to not accept an answer - but of course, you're free to do either way.