A number of people plan to travel abroad during the Qingming Festival long weekend which starts today. Financial planners recommend that using dual-currency credit cards is the most cost-effective method. "If consumers don't spend all of the foreign currency they bring back and convert it back to RMB, they may incur some losses from the difference between the buying and selling rates," the financial planner said. Consumers can carry a small amount of foreign currency for taking taxis and buying...