Ferrari does not recommend routine annual replacement of catalytic converters,spark plugs or fuel injectors. If someone is telling you this you are being misinformed or taken advantage of. If these areas are malfunctioning, that is a different story. Modern spark plugs last a long time in a properly functioning engine and catalytic converters under EPA laws are warranted for, I believe 80,000 miles- check your warranty book that came with the car. FWIW, the catalytic converters and fuel rails cost a bloody fortune in a Ferrari. Please read the books that came with the car. I have owned many Ferraris since 1974 and if you are believing this BS I have a Bridge to sell you in Brooklyn.