Twenty $ Bill Question

My best guess is that it isn't worth much more than a buck or two over face in that condition. Even a crisp uncirculated one might have a "book value" of perhaps $35.00 to $50.00 but really, how many people are going to pay that much?
I suppose certain Federal reserve banks are harder to find than others, certain signature series as well but this would generally be an interesting note that in time may increase in value but your initial money tied up in it might perform better investing $20.00 into something else.

Thanks guys