California's the test-bed, so go to your (online) references and pick a zip code: gm.ebay.com. Make your product choices, see the offers. It is almost like Carmax. I looked at the HHR around the zip code
90210 (yeah, I hear you in the back; pipe down!), and the ranges spanned from about $16.5k (lower trims) to $22k (SS) with a $2k rebate.The front-end presentation is the easy part. The hard part will be at the dealership. Assuming a lot of people are attracted to buying through the web site, will the final non-government fees discourage would-be buyers?