Where to buy tickets for the Beijing Airport Shuttle Bus?

1. You can buy the shuttle bus tickets inside Gate 7, T1; outside Gate 11, T2; outside Gate 7 or 9, T3.
2. You cannot buy the card at PEK. But you can buy it at any metro station, Customer Service Centers, CITIC Bank, Agricultural Bank of China, etc. You can find one nearby your living place.
3. Yes, you can keep it when you leaving the city. Don't worry.