If you are buying a F1 with any mileage - I'd budget for a replacement VCU. People on here have thought the VCU appeared OK when driving and reversing on lock, but the VCU was in actual fact toast - so on just a test drive its highly likely you won't pick up on anything. 70K miles is the recommended replacement interval by LR but as stated lots last a lot longer, while other fail much sooner. It the prop/vcu support bearings aren't giving any jip - they should be good - if you do replace them - don't do it with cheap ones - or you will be doing the same job very soon after.
Going by this forum, lots of nigglie problems can creep into the TD4's fuelling system from the lift pump (which may be why
@Skinny Mike suggested taking it up to 70). They can occur at any time on any car regardless of maintenance history. Most are not expensive fixes but diagnosing the problems can be difficult.
If you start getting injector problems, which can happen on low milage cars, they get very expensive to replace.