dear all, where do i get taxi in Beijing Capital airport t2 after 3am? is there any coupon for taxi from t2 to QianMen?

There is a certain park lot for the taxis at the airport and you can easily reach there by following the direction boards. The taxi fare is around 120RMB.
There is no coupon for the taxi from T2 to Qianmen.
You can ask the taxi driver to charge by meters. If he does not use the taximeter and charges higher than the price I tell you, you may complain to the taxi company.