how much $ would u offer this guy? (used walter woods 100 wt)

here's the Ad I found..
I have an older Walter Woods amplifier, the 100 watt kind (@ 8 ohms). 2 channels (I think one is voiced for acoustic, the other for electric).
Front panel left to right is:
Preamp volume, -o+ switch, bass, midrange, treble, -o+ switch, phase switch & channel selector switch, line out 1/4", line in 1/4", master volume.

Pots are scratchy, which is common on this amp. Otherwise, it works perfectly.

he sez"best offer",what would u guys offer?
havn't gotten the skinny on the model,year..or pics yet
trying to get a ballpark idea of what to offer.