translate this passage for me , please

As she stands guard beside the van, his friend draws her into conversation about their "special consignment". The goods might range from machine parts to miracle cures, priced at, say, $200 each unit. Then a passer-by, apparently unconnected to the pair, enters the scene and offers to buy some of the goods for $400 per unit. But the newcomer's offer is not readily accepted as the van owner is not around. So he leaves, promising to return in a moment to make the purchase.