I got a cold call for a temp position that I had not applied for. The lady asked me about my expected salary, and I flipped it and asked for the range. She said it depends on experience, and I said, "based on the experience in my resume where does that put me." She said she didn't know because she was not the Hiring Manager. She asked for my past wages, and I said I made a lot. I said I didn't want to lowball or ask too high. I told her I thought she knew the range, but she didn't want to provide it. She said "Wow". I told her that I was no longer interested. It wasn't going to work out. Good luck, and bye.
I don't recommend you work with these people. They are playing a game to lowball you and waste your time. When someone cold calls you, they better have a salary.