Cost of living in China is much lower than Singapore, especially in the Tier 2 & 3 cities. The rural areas and poorer provinces like Guangxi and Guizhou even cheaper.
China has now slipped into deflation. The worry is whether a Japanese style stagflation might ensue, if the CCP can't prop up the weak economy.
Singapore is the most expensive city in the world. Period. You have no cheaper cities or countryside to escape to.