Oh my goodness, if they are quilts they are always worth more than 50 cents!
Please get us pictures if you can, and otherwise maybe you have a quilt store you can take them too, if they can't help you with general range they probably can refer you to someone who can.
Prices vary by region, and always by style and condition of the quilts. As Dunster said, you should probably at least put them in a pillow case if you keep them in a cedar chest. And no moth balls ever!