2009 Porsche CayenneEnlarge Photo
The cheapest vehicles, surprisingly, were mostly import models. After Yugo, with an average of just $116 for those six parts combined, Geo ($154), Daewoo ($156). Daihatsu ($156), and Plymouth ($169) rounded out the top five. Curiously, all five of those brands either no longer exist or are no longer sold in the U.S. But GM had many older models that ranked among the cheapest.
The single most expensive model in the study was the 2008 Mercedes-Benz ML550. Several different model years of the Porsche 911 and the Mercedes-Benz S55 AMG filled out the top ten. Only by model, the most expensive vehicles were the ML550, the S55 AMG, the 911, the Mercedes-Benz CL55 AMG, and the BMW 750i. The Porsche Cayenne wasn't far behind.
Newer models have pricey parts...but there are exceptions
On an individual model basis, the Chevrolet Celebrity, Nissan Pulsar NX, Yugo Cabrio, Buick Reatta, and Pontiac 6000 ranked cheapest. Again, all of these models no longer exist (and date back to the 1980s), but all were still produced at the study's 1990 cutoff. Models from the past decade that boast a very low cost include the Daewoo Lanos, Scion tC, Saturn SC1 and SC2, and Kia Rio.
While this is useful information, you'll need to keep in mind that parts cost alone doesn't make a car cheap to own. Even for maintenance or repairs, the most significant cost is often labor.
You can increase your chances of keeping your motoring budget under control by looking at all the pieces of the pie, in overall cost-of-ownership assessments from sources including Intellichoice or Vincentric (Cars.com and others), which tend to include estimated repair and maintenance (including labor), insurance, and financing costs, in addition to fuel cost—all over, typically, a five-year period.
A quick check of those of some of the above-mentioned models with these sources indicated that pricey parts and high ownership costs do tend to go hand in hand, however.
Unless you're a fleet manager or small business owner simply looking to maximize the bottom line, you shouldn't choose a vehicle based entirely on ownership cost. But you won't want to completely ignore it either.