Hanoi, Nov. 5 -- Cross-border QR payments are widening Vietnam's tourism, retail and services links to international markets. But turning cost and technology gains into business results requires a broader acceptance network, transactions tied to sales management and end-to-end operational security. Cost cuts, more opportunities Ngo Xuan Bach, Chairman of the Board of Directors of City House Vietnam, said foreign tourists still mostly pay by card and cash. At many lodging sites, neither is truly convenient as cash means staff handling, counting, foreign exchange conversion, change and reconciliation while cards carry transaction fees and sometimes fail. QR codes, by contrast, are now common because they let businesses collect remotely, cut...