The price can sometimes tell you a lot. Do online searches at places like cars.com and trucktrader.com to get a general feel for prevailing prices. Compare the age, mileage and whether it's a half-ton, 3/4-ton or 1-ton, standard length or extended, bare bones cargo van or a passenger van. You'll probably see that vans below about $3,000 have high mileage and look like they've been beat up and neglected. The lower the price, the greater the chance someone is unloading a worn out pile of problems. That doesn't mean a high priced, low milage van is guaranteed problem free. It could be a lemon someone's trying to unload. 100,000 miles is nothing on a well maintained van. There are many still putting along just fine at 400,000 miles. Still, lower mileage is usually better.<br><br>The fact a van was a regularly maintained fleet vehicle can be a good thing or it can mean nothing. Fleet drivers sometimes abuse the vehicles because, eh, it's the company's problem, not his. "Regular maintenance" can sometimes mean "constant patching up of broken stuff to keep the pig on the road a little longer."<br><br>Also, the engine isn't the only thing that might need replacing on an old van. The transmission, the bearings and bushing in the suspension and steering, the cooling system, the A/C, brake rotors/master cylinder/brake lines, shock absorbers, exhaust system, gas tank & fuel lines, all sorts of electrical systems, rust/corrosion/metal fatigue, leaks of essential fluids going out or water getting in...