This Beautifully Obscure 1957 BMW 503 Bertone Cabriolet Is Looking For A New Home

BMW has never been particularly fond of letting Mercedes-Benz get all the glory. So in the late 1950s, after seeing what its arch-rival had done with the 300 SL, the Bavarians and their US importer set about marketing a stylish and luxurious convertible of their own.

They came up with two ideas, and put both into production. One was the 507 that we know well as the inspiration behind the Z8 roadster that followed decades later. The other was the little-known 503.

Based on the 501 and 502 sedans, the 503 was less sporty than the two-seat 507, but arguably more elegant. It came in coupe or convertible forms, the latter offering a rare early power roof mechanism. Unfortunately neither the 503 nor the 507 were particularly successful, commercially speaking. This compared to more than 3,000 examples of the 300 SL that Mercedes made, BMW ended up producing only 252 examples of the 507 roadster, and 413 of the 503 between the coupe and cabriolet models.

The upshot is that the BMWs remain the rarer machines today, and the one you see here is rarer still. It's one of just 18 examples that were coachbuilt with special aluminum bodywork by Bertone for the US market, and clearly stands the test of time as a classic beauty, combining German engineering and Italian design.

Having won its class at the Amelia Island Concours d’Elegance and awarded Best in Show at the Santa Fe Concorso, this rare matching-numbers cabrio is now consigned to Bonhams for its upcoming auction at the Quail Lodge in Carmel, California, during Monterey car week. Check it out in the gallery below courtesy of Bonhams/Litwinski.