The cheapest discount for air tickets is 30% off. The details are as follows: 13: 50, 18: 35, 30% discount on Xiamen Airlines flight, economy class, 1400 yuan, tax: 90 yuan.

. The direct flights are 1260, Xiamen Airlines MF8377, 13: 50, 18: 35, and the rest have connecting flights. Although the cheapest ticket price is 1020, these two paragraphs, together with airport construction fee and fuel tax, are not cheap.

. There is no train to Nanning in Tianjin, and there is no direct flight to Nanning. The train from Beijing to Nanning takes about 300 hard seats and 450-500 sleepers, and the whole journey takes 27 hours (I don't know how much it will take after speeding up).