That all depends on who you talk to.
I get emails all the time about "we want to buy your old equipment" and they list Nortel. But whether or not they will, don't know until you ask.
Most people would probably throw it out.
But if you find that person that needs it, it is worth something to them.
What exactly do you have?
What version software on the main unit?
And what do you mean by expansion cards?
They usually say expansion cabinet and then insert Modules in
side the cabinet.
So do you have empty cabinets? or modules that would be inserted?
Or both a cabinet and a module?

then it depends on the module.
what modules do you have? DSM ASM DTM ATM something else?
It will say on the front of it what it is.

As for the modules, those are also good for the BCM 400.

If CON is the opposite of PRO
Then what is the opposite of Progress?