There are very few problem areas with Dinos, but some things to watch out for are:
1) Rust - wheel wells, doors, fenders, rocker panels and the double sandwiched section just aft of the rear wheels
2) Second gear synchro - insist on driving the car when then transaxle has not been warmed up and notice how the 1-2 shift change is. I ALWAYS drive my car by shifting from 1-3 in the first 5 minutes before the gear oil starts to warm up (to preserve the 2nd gear synchro)
3) Flexible brake lines get old and swell - often the cause of weak braking
4) Dinoplex CD ignition box - known for failures, located in rear right trunk area
5) The Engines are very robust - a compression and leak down test are always prudent. Also, early cars had high camshaft wear - find out if there ever was an engine rebuild and if the cams were changed.
6) Correct seats - raised areas between inserts.
The seats on this car are shown as the Daytona style option and the most desirable. The Daytona style is indicated by "inserts" on the facia which have vent holes in them (those black parts on this car). The inserts should be vinyl with leather surrounding them in all other areas. The leather portions between the inserts should be significantly raised above the surface of the inserts. It is difficult to tell from the photos, but these are probably OK.
On other cars I see them incorrect as the surrounding leather is at the same flat level as the inserts. Photo attached to show a correct Daytona seat with inserts lower than the raised leather (ignore color differences)
7)alternator gets oil drips - check this area by putting the car on a lift and inspecting for any oil on or around the alternator
8)alternator gets oil drips - check this area by putting the car on a lift and inspecting for any oil on or around the alternator
Here is the typical source for the repro Campagnolo wheels, about USD$1000 for four. 206 / 246 WHEELS Superformance ferrari dino ferrari v6 ferrari v12 specialists 308 246 206 fiat dino 355 328
A few things
Note: While your prospective car is not a GTS, on the GTS one should look at the front visors. The GTS cars didn't have traditional rotating padded windshield visors but a different style that was retractable, fabric screen material on a spring loaded rod which you pulled-down. These often get old and inoperative, so should be checked for operational.