Table: Sisters under the Skin?

By building more than 60 models on four main platforms, or chassis components, Volkswagen saves up to $1.5 billion a year. That's great--as long as the customer can't tell. Here are four top VW sellers that share the same platform, even though they occupy different market segments.

SKODA'S NEW OCTAVIA offers great value for money under VW's Czech badge. Problem: The Octavia's sales may be eating into the Golf's customer base.

U.S.: Not Available

EUROPE: $11,600

VW'S GOLF, now in its fourth generation, is Europe's best-selling car despite a sticker price 20% higher than rivals in its class. The challenge is to keep it fresh and prevent lower-priced rivals from grabbing market share.

U.S.: $15,600

EUROPE: $15,300

THE VW BEETLE, a robust update of VW's original sedan, has registered a so-so performance in Europe. But its clever design and marketing have been a hit in the U.S.

U.S.: $16,450

EUROPE: $16,200

THE MUSCLEBOUND AUDI TT has been so successful that it has inspired a new car that mimics the TT's styling, the Lexus SC430 coupe.

U.S.: $33,775

EUROPE: $26,700

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