That depends on where you're from, demand, and how much the seller values their gun. Not to mention if they inclue extras with it. Around here I can find Gen 3's for like $350 or so, but that isn't with all sorts of extra mags, holsters, lasers, lights, etc. The Gen doesn't necessarily matter on price, it is another one of those it depends how much the seller and buyer values it. There are people who will pay top dollar for a prestine Gen 1 for collecting. You come to me with a Gen 1 I will offer you a minimum. Check Armslist, GunBroker, or any other sort of site. Or take a trip around your town and outlying areas and see what you can find.