I've got some laser equipment I'm looking to have someone take off my hands and I don't even know how much to ask for it. I was hoping to have some help from you guys!

One of them is a Coherent Model 42 (50W, IIRC) with PSU all in very good condition with mirror assembly/optics.
Then I have 2x 250W heads (1 mirror assembly, 1 PSU)
On top of this I have a CNC table, with and driver boards/computer board etc etc comes with Autodesk, and some other software.

Then I have a regulator, and 2 110cuFt laser mix tanks (full, $50/fill+)

The equipment was purchased for around $15k, and then another ~$3k put into the CNC Table, software, etc.

Can anyone help me estimate the worth of these? I was thinking $5k for everything (The optics/lenses which I have - spares I think are like $300/ea)

Photos: http://imgur.com/a/ZZ6D9

From my research I've found the Cylinders to be worth $300/ea, Found a listing for a busted model 42, without mirror box/optics for $1000. All of my equipment is in 100% working order.

Any assistance would be appreciated, I really don't want to ask too much for the stuff. I was also thinking about donating the spare head to a hackerspace, but we'll see.