Repairs can be inexpensive if you do the work yourself, its the parts that are expensive.
The bottom-ends of 308 engines can last longer than 100K mi when properly maintained (frequent oil changes), top-ends are very weak. Valve guides wear, which the least of problems can be excessive oil consumption, the worst, bent/broken valves. Ignition systems are sometimes very finicky, but again, regular checking/maintaining and some sort of electronic assistance helps. Carbs need a fine touch, but once done, keep their settings. F.I. is mechanical and complex, but more reliable than carbs. The first F.I. cars of the early '80's had some issues with weak piston rings, but they are still good cars.
Weak points of the cars in general is the electrical system.