The Ladies at Pittsburgh's Third Presbyterian Church (On the corner of Fifth and Negley Avenues in Pittsburgh) will usually let you name your own price, within reason at their biannual rummage sales. The next one is in October. They usually have good stuff. If you ask nicely they might also let you see the church's Tiffany Windows. (A friend is active in the church. It was my unwise response to, would you like a kitten? that led to my acquiring a gray and white furry hellion from her.