Warning lights: Make sure there aren’t any warning lights switched on, but also make sure that everything on the dashboard is working – indicators, hazard lights, headlights, brake lights.
Windscreen wipers: For safety reasons, the vehicle should always have good windscreen wipers and be filled with windscreen cleaner, which again keeps visibility as high as possible. You can get new wipers easily, but make sure they are good enough to begin with and you’ll save an expense.
Tyres: Again, this is something you could change, but they should be road worthy when you buy the van and the rims should be in good condition. If this is not the case, insist that tyres are changed before you purchase and drive away.