Very little actually. I bought the car from an enthusiast who had owned it for 11 years, but not driven it much in recent times. I replaced the cam belt ($17 part), the fan belt and fluids. As it turned out both of these belts definitely needed replacing.
The only issue has been the handbrake which will not work on really steep hills and apparently cannot be fixed. As a result I always leave it in gear on inclines.
A "rorty", taut and mischievous sports coupe that has character in buckets and still manages to lift its skirts and run with the modern cars.
The standard 1750 twin cam engine is fine, but responds really well to some modification. I have added twin Dellorto twin throat carbs, a polished 125T inlet manifold and K&N free flow filters, then had it dyno-tuned.
This resulted in an increase in performance from 85hp at the back wheel to 106hp (approximately 140 at the crank). And while this car is never to equal the contemporary sports cars, it makes it very nippy to drive and has a wonderful "raspberry" exhaust note. The brakes are superb, the handling excellent and the five speed box superb. And a decent sized back seat too!
If you are looking for one the over-riding requirement is rust - or the lack of it. Search long and hard for the most rust free example you can find, then grab it.
Reading your review brought back a lot of fond memories for me when I had my 124 (circa late 1969 early BC version with 1430 engine). If only Fiat would have the sense to reintroduce such a fine example of a sports coupe. Did you know that you can (could) get electronic ignition for your CC model. From memory there was a spot on the passenger side of the engine bay.
Did you fix the handbrake?
Was 2nd owner 1438 BC Coupe early seventies. Wife's runabout. Only comparative "smallie" was RX2 regards performance.
The thing you have to watch is that the front end is all hung in the sheet metal, and the place to find out if your Fiat's planned obsolescence has progressed to terminal is behind the inner guard at rear of front footwells. If it is sagging there, you have a problem. Most do, somewhere down the line.
Also rubber driveline "U" joint at rear of gearbox will wear if the beast is used enthusiastically.
Outside of which a magic sportif little weapon, with handling, exhaust note, attitude and brakes to match.
Almost the most fun you can have standing.
My Father had bought a new one in 1973. Red and the 1400cc, ordered with 5th gear. He only drove it Sunday's and he only did 9k. I got it in 1980. Used to race it on the track and on the road. never gave me any trouble except for some rust around the windscreen. People were in awe seeing it here. I sold it back in 1986 after I had done 140k. To this day I regret I sold it and if the guy had not wrecked it totally I would have bought it back.