Rear arm bearings, at a cost of around £300.
Ball joint.
Two of the three bolts holding the hydraulics pump together snapped in half!!! A new pump costs £350, and fitting cost around £80.
Since the failure of the pump, the hydraulics deteriorated significantly in quality, which no doubt would have been costly to repair.
Split water pipes.
Tracking, which caused extensive damage to the front tire's.
All of the wiring for the stereo (both electrical and speaker wires) were faulty. The stereo kept shorting out and eventually became unusable.
I owned this car for almost exactly a year, and I spent at least three weeks of that traveling to work in my girlfriends car.
I had no confidence in the vehicle at all. As soon as one fault had been remedied another one developed, and at no small cost.
Hey man... your Xantia is probably not a well-maintained car (resulting in loads of problems). Don't blame the car, man. My Xantia is the most reliable car I know...