Need 360 info...

If it's locked, take it for $50. That's more than he'll get is scrap, and it's worth that if it's a usable block. If it was sitting outside over the cold winter, dont bother paying anything for it. If there was any water in it (even from snow/rain/condesation) it's probably cracked somewhere. If you can get it for free, grab it up and tear it down.