One of the motor factors used to have the pre sprinter style merc van that was known as the starship enterprise that was going on for it's million miles
Most vans have had big miles, and if looked after they're fine. I had a VW T4 with 196k on it and it was as tight and quiet and fast a van as any others I've seen.
Last year I bought a Ford Transit Connect 1.8td with just under 200k as well, and I'm not sure how long it took to get to that, it was the slowest thing I've driven for an age. It was inexorably and inexplicably slow and started to fall apart so I offloaded it to the first person that was prepared to take it away.