They hold their money as they are just nigh upon bomb proof. They are the kind of van that you buy once and run forever. You don't need to sell them when you think they're getting on a bit because they're good for moon milage.
We have 5 on our fleet with the lowest mileage being 173,000 miles. Highest being 210,000 miles. 1 has had an engine but the rest have had virtually nothing (obviously ignoring service items). Just the usual alternator wiring repair and 1 had the gearbox out for the first time ever at 187,000 miles.
For 2.5k-3k you should get a reasonable 05 plate van or a mint 04.