I'm assuming that you mean a Rogers Cable digital box, and that you purchased (as opposed to rented) this equipment. This would also depend on the type of box. Here are the rates for purchasing the four types of Rogers Digital Cable boxes brand new:
Standard digital box: $99
Hi-Definition Box: $249
Standard PVR: $399
Hi-Definition PVR: $499
You can expect that a used box in good condition would sell for about half the price of a new unit.