BANG BO, Thailand—When the buses stopped coming in early 2020, it wasn’t long before businesses began dropping like flies. Souvenir shops were the first to fold. Then the hot-pot place let its lease expire. Eventually, even the 7-Eleven shut down. 

Now, this cluster of three-star hotels near Thailand’s main international airport is coming back to life as China reopens its borders. Neatly uniformed staff at Chor Cher, a resort that catered almost exclusively to Chinese tourists, come to work daily even though all of its 389 rooms are still empty. The walls shimmer with a fresh coat of paint and new furniture is in place.