I just got back from there. Gulangyu Island is a must-see. It's great to see the Sunlight Rock, the old buildings and the beach. When you arrive in Gulangyu Island, you can spend 1 yuan to buy a hand-painted map, which is basically something unique discussed by netizens. Also, it is cost-effective to buy an 8-yuan package if you go to several major scenic spots in Gulangyu.

if you book your accommodation in advance, there is no problem. We stayed in Hejia Hotel in Xiamen, and the accommodation environment and breakfast were good, and the price was around 2. If we stayed in Gulangyu's sanatorium with sea view, it would be a little more expensive, about 5, which was super big. Cheap ones should also be available. You can look at private hotels online, but you must pay attention to safety. Don't go to Gulangyu's food stall to eat seafood, it's not delicious. If you want to eat, there is a food city above the World Trade Center in Xiamen, where you can find some special things to eat. The seafood in the restaurants in Xiamen University is also good, delicious and affordable. The cost of the tour depends on how you spend your money. It's hard to say, you have to make a counter-offer for the souvenirs you buy.