Passenger Cars
Sedans come in three basic sizes: compact, midsize and large (or full-size). Market segments include economy, family, entry-level luxury, luxury and sport. Some models don't fit neatly into any one group.

Compact economy sedans cost $10,000 to $20,000. Midsize family sedans start under $20,000 and top off in the low-$30Ks. Large non-luxury sedans run from the mid-$20Ks to the mid-$30Ks. Entry-level luxury sedans run from $25,000 to $40,000. Anything above that is considered luxury. Sport sedans are spread across all price brackets.

For fuel economy you'll see four, five, six, eight, and even 12-cylinder engines in this group; turbo's are common. Compacts are the best bets for gas mileage, especially the gas-electric hybrids and diesels.

Sports Cars
Convertibles range in size from two-seat roadsters to larger four-seat luxury models. The majority of convertibles on the market are luxury-brand vehicles, although there are still several affordable drop tops on the market.

The cheapest convertible runs in the low-$20,000s while the most expensive luxury models can run well over $100,000. There are several convertibles that cost less than $35,000, but the most populated segment resides in the $35,000-$80,000 price range.

For fuel economy most midsize models use four- and six-cylinder engines, while more expensive luxury-branded convertibles generally use V6 or V8 engines. Four- and six-cylinder models can get good mileage in the mid-20-mpg range, but most eight-cylinder drop tops turn in less than 20 mpg.

Luxury Vehicles
In the class of luxury cars, you will see four basic sizes: Upscale sedans, Luxury sedans, Mid sized SUV's, and Large SUV's.

Upscale sedans run from $25,000 to $40,000. Luxury sedans start around $30,00 and top off in the low $100,000. Mid sized SUV's run from the mid $20,000 to the mid $50,000.