Why do I start at $150....because that's HALF of the cheap roundtrip fare, for IAH flights. For flights to EWR I start at $250, once again based on the cheapest round trip fare. I hold onto volunteer's boarding passes and do not release their seats until I am positive I'm oversold. If I don't get anyone for the lower amount I increase the amount by $50 until I do. So far I have been very successful but then again I do the red-eye flights and those that volunteer are offered the next day's flight, hotel for the night and the VDB...not such a bad deal.