Consulting firm Runzheimer International has released a study that suggests purchasing and operating a Toyota Corolla wouldn’t cost much more than simply operating a Cadillac STS.

The STS topped the passenger-car list of most expensive vehicles to operate, followed closely by the Lexus LS460 and Audi S4. Considering fast-rising fuel prices, V8 sedans are obvious per/mile abusers of your wallet. (Assume the exemption of $200K, 10mpg Bentley’s and their ilk.)

The Corolla CE is the least expensive to operate, followed by the GLS model of Hyundai’s Accent and the Chevrolet Cobalt LT. The Corolla’s estimated yearly operating costs of $7,933 – based on fuel economy, insurance, depreciation, taxes, and maintenance over 15,000 miles – are $11,604 lower than that of the big Caddy. There wasn’t even a truck or heavy ute that approached the STS’ frightening numbers.

Should we expect the smart fortwo to make a dint in next year’s most inexpensive operators? With an $11,590 base price, the obvious fuel efficiency advantage, and apparently high demand (protecting second-hand values), the money-losing brand might just provide you with a money-saving option.

$$$$$ – Your’s