If you don't have a mechanic mate or a local member that's not exactly easy though. 
And all diesels smoke...its when you can see it in the mirror you know its too much.
Also check for it being a lot flatter than you were expecting, usually means the MAF is knackered as they nearly all are now. Previous owners don't notice though as they wear out over time rather than suddenly.
Check it starts well without all the dials flicking.....mine had a bad earth that I never could find.
And let it idle when its warmed a bit - if it hunts there's a dodgy sensor somewhere.
Oh also, listen for the thrust bearing whine, it'll be pretty obvious and rises with revs.........you don't want an exploding thrust bearing, mine was close when I broke it....
And all diesels smoke...its when you can see it in the mirror you know its too much.
Also check for it being a lot flatter than you were expecting, usually means the MAF is knackered as they nearly all are now. Previous owners don't notice though as they wear out over time rather than suddenly.
Check it starts well without all the dials flicking.....mine had a bad earth that I never could find.
And let it idle when its warmed a bit - if it hunts there's a dodgy sensor somewhere.
Oh also, listen for the thrust bearing whine, it'll be pretty obvious and rises with revs.........you don't want an exploding thrust bearing, mine was close when I broke it....