The dealership that I leased my Crossfire from has a formal agreement that specifies an additional $1000 for your trade-in if the logbook is up-to-date and all work has been performed at that dealership. That practice is becoming more common across the US. There is an obvious "hook" to promote service work at the dealership, but...
Many DaimlerChrysler dealerships are now involved in the DCX Certified Used Car program, which offers an 80,000 mile 8 year warranty on any Certified Used Car purchased at the dealership. It costs a dealer much less to "certify" a used car that has been maintained at or beyond manufacturer requirements, so they can afford to pay more for that trade-in.
Import owners have known for years that regular maintenance not only pays immediate dividends in performance and reliability, but can certainly increase the vehicle's value at trade in. Domestic owners are just now beginning to discover that this is true in many cases.
Fritz