No one really knows how many were built. It was an option/trim package. I think 500 was the minimum necessary to qualify to race, but there was rampant cheating in the ETCC at that time, so to say there was X number of cars built would be a guess at best.

They just seem to be far too common for ONLY 500 to have been made. There's nothing special about the car that would make it more valuable, short of the "package" that you get (intercooler, flat hood, rare grille). It's not that hard to find the parts to make a copy, and they're difficult to verify. Those who know them well can spot small details, but I wouldn't be too worried about buying a '83 242 and thinking it was a homologation car when it wasn't.

There were quite a few 242s built for the ETCC. I think there were at least 6 factory cars, plus private teams. If you ever did find one for sale, it wouldn't look like the US model from '83. The front sheet metal & lights were changed, and the chassis was heavily modified.

Some more info on the ETCC racing effort:
http://bartonharness.com/Volvo_Group_A_Racing.html
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