Porsche Classic 911

The first 911s ran a 2.0-litre air-cooled flat-six that grew to 2.4 by 1972. Cars built through 1968 use the short wheelbase; from 1969 Porsche stretched it by 57mm, which transformed the handling and split the market into two quite different cars that share a silhouette.

Values here are driven by originality more than condition. Matching numbers, documented history and the absence of structural rust separate a six-figure car from a project — and rust is the one thing a photo set will not tell you.