Ask for a vehicle from hotel to the Capital airport.

I stay at Beijing Zhongan Inn Andingmen Hotel. I'll travel back on Thursday 19 April 2013. My group is 4 peoples with luggage. So I think that I need a van to drive me to the airport, one taxi should not enough for me and two taxis are not safe because another three cannot speak Chinese nor English. So how can I get a van to bring me to the airport.