Don't know how to directly answer your question, but BMW's really keep their value and dealers make a killing CPO. Of course, you can count on the car you are getting being up to quality standards. The way I would look at your question is look at the ultimate dealer price (see if they are willing to deal) and compare that to a build at the official bmw site and go from there. Too many times I have heard about and actually seen people go CPO when for just a few more c-notes to gerr, they could have gotten new. Good luck!