There are many overseas customers coming to China and they want to know the cheapest sim card for local calls and data package
Well actually there is no abosulutely answer for this because it really depends on the person himself
We have China unicom AND China Mobile,plus China telecom
They all have its own advantage
China Mobile is more stable in signal,China telecom is best for internet, China unicom is considered as cheapest but however,it still depends on their package.
Different company offer different package,some suitable for more calls,some suitable for data,some good for many messages. So you have to find out what the package include first. No matter which package you choose,it will have monthy rent always.
Hope it helps