The 147 is rather blessed from the normal alfa problems, the weak point is definitely the engine. Check so that they have made frequent oil changes, listen for a diesel sound when idle (this is common and is the cam-variator making that sound, and if so it needs to be replaced) also check that they have changed the timing belt INCLUDING tensioner and wheels and also the belt and tensioner and such for the balance axels. If all that is ok, they usually don't give you alot of grief.
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