the orange light is the engine management light ,
depend on how much its going for ?id say would determine wether to walk or not
you have no real reference to how many miles its done or service history
i would walk .. some good ex fleet vans come up at auction with a good history
just the other week my mate bought a vauxhall combi van 51 plate £2200 plus the dreaded and only had 86thou on the clock