Symbol “oil leak”

I’m hoping to replace my Symphony with a slightly newer Symbol, and have been looking at ones for sale at the moment.
I’ve seen at least 3 from around 2008-2010 which were of interest. All had 2.2 diesel engines, and all have noted on previous MOT history that they have an “oil leak”.
Can anyone explain to me where this leak might be from, and whether this is a known problem with the Peugeot Boxer 2.2 diesel?
Should I be concerned about this, and avoid these vans?
Thanks

Unfortunately it's impossible to infer anything from a description of "Oil leak". It could be anything from careless filling last time the oil was changed to a hole in the sump, and anything in between. And it's likely that an MOT tester won't confine such a comment to the engine oil, so it could refer to power steering fluid, transmission fluid and possibly even brake fluid, depending on the circumstances.

Without further detail from the seller, the best you can do is to inspect the vehicle carefully, or pay for the likes of the AA or RAC to inspect it and report on what they find.