When shopping at auctions, if you get the catalog in advance, search eBay and Google for everything, and find out what the items are selling for on the web. There were a bunch of things I didn't buy because I knew it was possible to get them cheaper elsewhere.

kproche pointed out, though, that if we even only get 300 pages off the printer and it dies, we're still not out any more than having 300 color fliers printed at a copy shop.