The rental yield in Shanghai is about 2% now, a serious bubble! It’s close to the return of 1 year fix deposite. Considering the most recent CPI figure was over 2%, the rental yield is actually negative. This will affect the Chinese economy in many aspects, if not a pending crash in the economy. Be very cautious at investing in any assets in China now.
If you want to know more about the property bubble, look at the following link.