Having seen how expensive a cheap car can really be (that's all my mom could afford as a kid, and did that come back to bite her regularly), I won't go lower than CPO when doing a purchase. I bought used without a CPO exactly once, and I was very glad it got totaled before I had to put a bunch of money into it (and that insurance said it was worth more than I owed so I got a decent down payment on the next one).