Don't take any notice of him. :
He probably couldn't afford one or something.
Probably has a Fiat.
If you're abusing it like delivery drivers for 50,000 miles a year at 100mph it may give more problems than some.
I however do 5,000-odd work miles a year, and after 3 years when I exchange it I will have done 15,000, 20,000 at the most.
I doubt most window cleaners do that much more.
I hardly think it's going to fall apart in 18-20,000 miles. :
You're perfectly safe with one, and it's the best van to drive, along with the new Transit.