Hi all , first post , I'm actively looking at buying a focus hatch 1.5t 150hp Ecoboost, prefer the 1.5 due to it being a chain driven engine and not a wet belt , my question is , is there anything common about these cars , not just the engine , anything else as well that is a common issue that I should look out for ? Thanks 

If the Battery has not been changed yet then it will likely be on last legs at 4 years old.

I have had the same car as you are looking at since new and I love the Engine, same Torque as my old 1.6 TDCI but a lot faster. 

Door seals will be hanging off at some point.  Battery faults are very common as Tizer says, not just for starting the engine but it prevents things like heated screens, keyless entry and even air conditioning from working when the charge drops too low.  We've seen a few clutch faults on the Mk4's though fewer than there were on Mk3's.  Creaks and rattles are also pretty common, the Mk4s don't seem to have been as well built as the Mk2's (although some will claim the opposite on here!).  And faults with Sync & nav seem to pop up quite often as well.

There is still a wetbelt for the oil pump on this engine, just so you're aware.

Overall, I'd say that is the best engine choice in the early Mk4s, and if you get one that's early enough, you'll get independent rear suspension as well.  Later models moved to twist beam like the Fiesta.

19 hours ago, Edgie70 said:

I'm actively looking at buying a focus hatch 1.5t 150hp Ecoboost, prefer the 1.5 due to it being a chain driven engine and not a wet belt 

All Mk 4 petrols 1.0 and 1.5 have a revised engine with chain cam drive , but wet belt for the oil pump, as Tom mentions.