I just won a complete copy of DW7 today for about 25 dollars + 3 shipping, slightly less than what it sells for generally, which is about 35-40. I also placed bids on the following copies which are going for cheap, but withdrew them because I'd like some other person to have them. If I could win my copy fairly cheap without anyone trying to outbid me, there's the possibility you could win one of these for even cheaper. Take a look:
http://www.ebay.com/itm/181348250316
and
http://www.ebay.com/itm/301121638621