Start with what the Buick Opel is: a car with gasoline engine, built from 1974, as the oil crises and the first emissions rules rewired the industry. What it meant takes a little longer.
The hardware
The engine is gasoline engine. These are manufacturer figures carried by Wikipedia and Wikidata, not road-test measurements.
Family and rivals
The cars a buyer would have weighed it against include the Jeep Cherokee, the Volkswagen Golf, the Lamborghini Countach. Its Buick stablemates include the Buick First Call and the Buick Funeral Car.
Owning one today
There is no federal ownership record for the Buick Opel — it predates the complaint database or was never sold in the United States — so MotorJury publishes no running-cost figure for it. For a car of this age the price is set by the collector market and the condition of the individual example, not by a formula.