Salary expectations: how do you answer?

A recruiter asked for my salary expectations on a first call as I look for work as a procurement assistant. I looked up ranges in St. Louis and they vary a lot. How do you research fairly?

I gave a range based on local postings and said I was flexible depending on the whole package. They did not push back.

Asking about the range for the role first worked for me. Some recruiters share it.