Advice removing water stains on front curtains

When we bought our coach, the front curtains were old, stained and sunlight-deteriorated as well. After looking into several ways to do it, we finally decided to get a local seamstress to make us new curtains. I found the new curtain track tape online through PPL. All total, less than $100 and we have band new curtains that will probably last us for the rest of the time we have the coach.