Here's a fun fact (and deal breaker):

What Voids Your Entire Warranty?

Salvage title: If your car was in a severe accident and was given a salvage title or declared a total loss, your entire warranty is voided. Unknowingly buying a salvaged car isn't an issue with certified pre-owned vehicles, but keep this in mind if you are looking to purchase a late-model used car from a private party or independent used car lot. If you are unsure about a car's past, we suggest getting a vehicle history report.

Source: http://www.edmunds.com/auto-warranty...-warranty.html