as said above mate belts need to be changed at 100k or before if you got the cash better to be safe than sorry had mine done on my old st170 at 80k make sure the clutch is not slipping
very expensive job £700 to £1.100 depending where you have it done rust under the door mirrors and under the number plate light strip on the hatch (common fault on all focus)
lambor sensors give up £70 each (2 of them) heat shields under the car come lose and rattle like fuck had mine 5 years and all i had done was belts and clutch great cars