Its funny you say electrical faults - my brother has a 1.2 55 plate extreme 4 and within 24 hours of buying it, it ended back at the garage and had to have a new ECU fitted.

Then it started running badly and cutting out - found the Lambda was no good and this needed replacing.

Then both ABS rings cracked in half resulting in a big knocking noise when braking - it is all fixed now and runs lovely but was a bad start to a new car.

Other common faults are engine mounts on the 172/182's, ABS rings on any model, electrical faults - accelerator pedal rubbing the wiring, ecu wiring rubbing through, ecu dying.

Touch wood mine is ok