The memory alone costs about $250 new on Dealram.
He also said "1.4 TB HDD's" which I assume means two of them (and probably 1.5 TB as I've never seen 1.4 TB). Those are over $100 each new on Pricewatch.

The Pioneer DVD DL is worth about $50 if you consider the brand name.

So that's around $450 - $500 in upgrades.

Click to expand...

Thats all very true, but the system as a whole isn't worth that much. Sometimes it makes more sense to part out a system than to sell it as one unit. If it were a quad 2.5GHz or even a highly desired DC 2.3GHz model (because its the fastest to run without the liquid cooling) the price is higher. If he can find someone to pay that much, then thats great. But with brand new Macs and even faster G5's for around the same price or less, its a hard item to sell for what it may be truly worth.