three3x3evils

I've been doing a lot of ebay hunting lately, as suggested by a few people here...looking for a used matrix to get into tourney play at an affordable price. However, I'm finding really broad price ranges...$150 all the way up to $500. I'm kind of lost on that and am really unsure if I went for a bid on a $150 deal if I was getting ripped off for junk. It says check their ratings and stuff but it usually only has one review. Anyway...what is a good price for a used DM4 or DM5, either stock or up'd?

-Thanks

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