We are looking at getting a newer Diesel Ford Focus(between 2007 and 2009), and was after some advice of common faults etc. I have heard that the 1.6 and 2 ltr diesels have problems(turbos and DPFs etc) , and that the 1.8 ltr, although older, is the better option. Also, what type of model is it worth getting, as obviously, each one has its own downfalls.

I'm not a diesel owner but the guys on here think the 1.8 id the one to go for as for trim zetec or above all fords have certain common issues ie water leaks from rear lights and spoiler so check the spare wheel well aim to get 2 keys most come with one so bater £100 off for a second key to get cut and programmed check it runs fine and odles fine check all the electrics also if you do a lot of short trips less than 10k a year or lots of towm driving dont get a diesel as it wont be worth it

Only problem i've had is a dirty fuel filter due to a missed service.

The 1.8 is dependable and tough.

As Arthur says, check for water ingress and walk away if it only has one key.

He might do a lot of walking lol almost every ford only seems to have one key as silly as it is

2008 1.6 TDCI here. Done 20,000 miles in it with no issues at all. Father in-law has a 2006 1.6 TDCI that's just coming upto 90,000 miles, also no issues. If I were buying again I'd probably get the 2.0 TDCI, but then if I had that, I'd probably still want something faster!