I don't believe California smog checks test to higher standards than a federal car was designed for. An untampered federal car in a good state of tune will pass easily. One caveat is aftermarket cats. Some shops won't test a car with uncertified aftermarket cats but that's better than failing it.

Does your daughter work on her car? It's difficult to find a shop that'll take proper care of a 124. Forget MB itself. Inland empire, this time of year, a 124 AC system, particularly an R12 system running R134a will barely cut it. Unless she buys a fixer upper, the seller is responsible to provide evidence of a smog certificate no older than 60 days of the date of sale. That doesn't mean much in a private party transaction. Good luck getting your money back if you didn't check before closing the deal.

Sixto
98 E320s sedan and wagon