were Fiats expensive in Europe in the 1970s

not realy

everything became very expensive in 1973 when the oil crisis happened

No, because it was the time of the economic boom just before the petrol crisis in middle 70s.

For Americans and Canadians they were cheap as dirt - however for a European to buy a Fiat it was like Westerners buying a comparable 4 door sedan - depending on your salary very few families of 4 could afford any car in the 70 is let alone a cheap Fiat. Fiat is have only come into the Upper Crust of Vehicles in the last 15 years with Young People wanting it.

Only to own and maintain.

l owned a 68 Fiat. If they were any cheaper, Fiat would have paid me to take it.

No, they were pretty cheap.